German Politics in general are something that is rather incomprehensible to outsiders, and discussions about it have a very notorious reputation on AH.com. Hence, it shall be explained here a bit.
Germany's 1949 constitution, the “Grundgesetz” (Basic Law), provides for a federal parliamentary republic which in many ways stands in contrast to the preceding 1919 constitution that formed the Weimar Republic. The Federal Chancellor (Bundeskanzler) is only responsible to the Federal Diet (Bundestag) which he's elected by and which in turn can only dismiss the chancellor by electing a new one. The constitutional strengthening of German chancellory and the customs set up by the first Federal Chancellor Konrad Adenauer provided for Germany's political system to be labeled as a “chancellor democracy”. The head of state, the Federal President, is quite weak compared to its predecessor in the Weimar Republic.
As in any good federation, its states possess a viable amount of political competences, though there are not as numerous as in e.g. the US or Switzerland, but they still contain among others the almost complete control of educational and police affairs. The varying financial potency of the various Länder constantly gets compensated by a complicated means of federal financial compensation (Länderfinanzausgleich) to ensure comparable public services in all Länder.
And as in any good federation, the directly elected chamber of parliament has a counterpart representing the states of the federation (lands, or Länder in German). In Germany it's the “Bundesrat” (Federal Council), factually being somewhat of a second chamber of parliament, but not in theory as its delegates don't possess a free mandate like the delegates of most second chambers of parliaments in the world and aren't elected in any way, but hail directly from the Länder governments and therefore have an imperative mandate. These delegates represent the whole of their state government and can only vote en bloc for their state, necessitating a consent among each state level government on how to vote on which issue in the Bundesrat. Non-consential votes can bring state governments to the brink of dissolution. India has a comparable federal legislation process.
Depending on which level of goverment holds the compentence over an issue, Bundesrat has varying powers in legislation. Exclusively federal laws passed by Bundestag can only be paroled by Bundesrat and sent back to the Federal Diet which then is to overrule the parole by the same substantial majority (absolute or two thirds) as the Bundesrat used to parole them to get the bill passed, here it's somewhat like a republican version of the House of Lords. If the law in question is a matter of “rivaling legislation” (“konkurrierende Gesetzgebung”), meaning that federal and state levels both have a say in that matter, the bill needs the same level of consent from Bundesrat as from the Federal Diet, these are among others constitutional amendments, international treaties and of course differing financial laws.
These laws of “rivaling legislation” unfortunately make up for more than a half of all federal laws, many of them very vital, though there has been progress of unweaving some matters of policy. Combined with the fact that there's always a state election somewhere in Germany and voters don't hesitate to also punish the federal government with their vote, you will constantly see differing majorities in Bundestag and Bundesrat. This may be seen as a German variety of checks and balances similar to the different flags that President and Congress wave in the United States, but this has also been heavily criticized as a cause of lazyness or unwillingness in reforms (Reformstau, traffic jam of reforms). This will also make the German system of political coloration even more interesting.
The CDU (“Christlich-Demokratische Union” - Christian Democratic Union) is the main conservative party in Germany, and are successors to the Weimar era Zentrum party. They (until recently, that is, 2021) ran Germany as senior member of the incumbent coalition, and the last German chancellor, Angela Merkel, also hails from the CDU. The majority of chancellors of the Federal Republic also have been hailing from the CDU (Konrad Adenauer, Ludwig Erhard, Kurt Georg Kiesinger and Helmut Kohl).
In Bavaria (where else?) the CDU does not run, but instead the CSU (“Christlich-Soziale Union”, Christian Social Union) does, which in return does not run outside. CDU and CSU form a common club in the Bundestag, the German parliament. One could hence describe the CSU as the CDU's Bavarian section, but that is not entirely true as it does have a completely own party apparatus. The CSU is on average far less moderate and more conservative than its sister party. The split of CDU and CSU dates back to the earliest days of the Weimar Era when the Bavarian section of Zentrum party broke off to form the Bavarian People's Party whose immediate successor is the CSU. The CSU has nearly always run Bavaria except for an SPD-lead government in 1950-54, and has done so with an absolute majority from 1962 to 2008, after which it had to join a coalition with the FDP (wherein the CSU, as Horst Seehofer explicitally told, was meddling like a virgin due to lacking prior experience). Attempts to have a CSU chancellor (Franz Josef Strauß 1980 and, äh, Edmund Stoiber in 2002, and, äh, Strauß even declared himself, äh, winner before he had to realise, äh, it was not so) have failed so far. Maybe Söder will have good luck.
The parties' black colour (different to the blue usually associated with conservatives in Europe) is due to its Zentrum heritage, and is the party of the pre-WW1 catholic parties, themselves taken from the catholic priests' black robes. When referred to as a collective, CDU and CSU are called, both ending with “Union”, as Unionsparteien or simply Union.
The SPD (“Sozialdemokratische Partei Deutschlands” - Social Democratic Party of Germany) are the other big party of Germany - approximately comparable with the Social Democratic, mainstream Socialist or Labour Parties in other European countries. They take pride in being the oldest currently existing party in Germany (well, besides the still existing Zentrum, which is merely a splinter of a splinter anymore, though) - being formed in 1863 (with a short intermission during the Nazi era when it was forbidden). As thus, of all parties currently in the Bundestag it has the richest history. The SPD became increasingly popular during the Kaiserreich, was the main force behind the 1918 revolution, and had one president (Friedrich Ebert) and three chancellors (Hermann Müller, Gustav Bauer, Philipp Scheidemann) in the Weimar Era, not to mention the long-time minister president of Prussia (Otto Braun) - oddly few, considering it was the biggest party most of that time. After the KPD (communists) had been expelled from the Reichstag (the Weimar Republic parliament), the SPD delegates were the only ones to vote against the Nazi Enabling Act (Ermächtigungsgesetz), despite SPD presence in parliament.
In the Federal Republic, the SPD has had four chancellors - Willy Brandt, Helmut Schmidt, Gerhard Schröder, and Olaf Scholz. By the Godesberg Program of 1959, it officially shed its marxist roots, though actually the party already hadn't been that Marxist anymore even back in the old Kaiserreich. Its main political points in the Federal Republic were the welfare state and better relations to the East Bloc.
Historically, the SPD's strongholds of course always were the urban and industrial areas, in the Kaiserreich mainly the Ruhr Area and Saxony. This has somewhat changed now - the Ruhr and also the Saar as the second West German former coal area are still SPD strongholds, but Saxony for example regularly votes CDU absolute majorities. Generally, the SPD is also strong in Northern Germany, especially Hamburg, and also has governed most of the time in Hesse, while being very weak in the two Southern states.
As of June '18, Andrea Nahles became the first female head of the SPD. Didn't last very long either. After that, they tried an experiment and elected a Doppelspitze (“double… head?” – a concept we only knew so far from more alternative parties like the Greens, the PDS, and the… AfD) of the two nonentities of Norbert Walter-Borjans and Saskia Esken. The party has had a high turnover of federal leaders since Schröder left politics, and even before that, leaders changed every few years since Willy Brandt retired, so don't count on this info.
The FDP (“Freie Demokratische Partei” - Free Democratic Party) is one of the principal minor parties on the federal level and junior partner of the incumbent coalition, founded immediately after WWII. It is the main liberal party of Germany, and just as the CDU roots are the Zentrum, the FDP's roots are the liberal movement in Germany, which before the era of the Federal Republic had traditionally been split in right or national liberals and left liberals or progressives, with ever varying parties (DVP and DDP in the Weimar Republic, respectively). It is worth noting that “liberal” of course means something very different in the European sense then it does in the American sense. Americans would probably describe the FDP as moderate libertarians - that is, they represent classical libertarian positions of being pro-business and pro-social rights, while having none of that scary dogmatism of many American libertarians.
In the pre-reunification Federal Republic, the FDP made or broke governments. Despite being the smallest party in a three-party Bundestag, their choice with whom to ally decided everything and over the pre-reunification time they switched partners two times, both during running legislative periods (i.e. in between elections). Also they acquired an ill reputation of being “the party of the rich”, and it certainly is true that the party is strongest in areas of business concentrations and areas with high income levels. This became especially the case after the party all but shed its left wing in 1982, when they changed sides (another thing they're often attacked for). Nowadays they mainly focus on the pro-business parts of their agenda, and mostly exclude the possibility of alliances with the SPD, being firmly in orbit of the CDU.
After reunification they had a rather heavy crisis, falling short of the five percent clause in many state legislatives, and only keeping above it on federal level due to strategical voting by CDU followers. In 2013, even that failed - yes, for four years, Germany had a Bundestag without the FDP, a novum. However, they managed to come out of this and nowadays look rather good, like all of the
three four smaller parties in the Bundestag.
For some time, FDP head and German foreign minister was the openly gay Guido Westerwelle. It would have been interesting to see said gay foreign minister at the White House still having born-again Christian Bush in charge. Now we'll never know, especially since he's deceased now…
The Greens (“Bündnis 90/Die Grünen”) are a relatively young player in German politics that emerged in late 1970s and early 1980s from the pacifist and environmentalist movements of the era. The Alliance '90 was a consortium of anti-SED East German parties that emerged just prior the reunification and joined up with the Greens. It is worth noting that all other parties simply absorbed their East German counterparts without any name changes. The Greens were at first openly discriminated against in the Bundestag (with them being denied some rights a parliamentary club usually enjoys), but managed to establish themselves in the opposition nonetheless. Their first government participation was in Hesse 1985, being junior member of the SPD. The Hessian section was led by Joschka Fischer, a moderate who would later become the party's most important member. Under him, the party also firstly entered federal government in 1998, again as junior partner of the SPD, under Gerhard Schröder.
Due to his influence, and due to being in government now, the party moderated itself, against much resistance from the party base. While many complained the party had lost its profile this way, it opened up new possibilities of coalitions: While before the Greens could only ally with the SPD, coalitions with the CDU now are rare but possible. The pro-business FDP remains the environmentalists' archnemesis in a rather petty (by both sides) feud. Didn't stop them forming a “traffic light” (see below) coalition in 2021 together.
Oh, and in their early years, some alternative groups that'd later join the Greens called themselves “bunt” (colorful) - let's count that as a color as well.
Die Linke (“The Left”) is the current German party “left of the mainstream left party”, though despite popular accusations from the CDU it cannot accurately be described as Communist. It was formed by the fusion of the WASG, a recent (post-2000) leftist SPD splinter, with the Linkspartei (Left Party), itself a renaming of the PDS (Partei des Demokratischen Sozialismus - Party of Democratic Socialism).
The PDS meanwhile was the legal successor of the SED, the Sozialistische Einheitspartei Deutschlands (Socialist Unity Party of Germany) - that is, the dictatorical party of East Germany. While it was mostly the reform wing of the SED that made up the SED, the party did inherit all of the SED's assets - and its bad reputation. The party was shunned by the rest of the political spectrum for years, but managed to have some successes (even large successes) in East Germany by representing itself as an East German regional party. It was not able to gain any foothold in the West, though, and even the successes it had in the East were largely due to the personal investment of its most prominent member, Gregor Gysi, a skilled rhetorician with much personal charm.
The WASG meanwhile was the project of one Oskar Lafontaine, longtime leader of the SPD's left wing with a personal power base in the Saarland, where he also was Minister President for some years. As this shows, Lafontaine (often pictured in political cartoons as a Napoleon, for being of similar size and having similar ambitions and coming from France-near Saarland) enjoyed quite a career inside the SPD for years - amongst other things, he led the party for a few years and tried to become chancellor in 1990 but failed miserably. During that time, officially the SPD was ruled by a “troika” of him, Schröder and Scharping (forget about him, Germany has, too), but Schröder, the champion of the SPD's moderate wing, eventually won out and became SPD chancellor, as we know - something Lafontaine took rather badly. Despite becoming Minister of Finance in Schröder's government 1998, he withdrew from all offices in 1999 and left the SPD in 2005. He then set out to form his own party, the WASG (“Wahlalternative für Arbeit und Soziale Gerechtigkeit” - The Electoral Alternative for Work and Social Justice). The WASG was from the beginning thought as a provisorium until unification with the PDS could be achieved. Which still strangely took some years, party bureaucracies at work.
Of course, the PDS was overjoyed to gain a foothold in the West, and so the merger eventually did happen in 2007. Since then, the SPD has lost dramatically in polls and elections, as its left wing flocks to the new Die Linke. Additionally, it has created a huge spat inside the SPD about whether to ally with them or not. Before, the SPD had allowed its Eastern sections to cooperate with the PDS, but forbidden all Western sections and the federal level to do likewise. Now, though, that consensus is broken up, but there are still some SPD members with acute cases of paranoid commiephobia who exclude all possibilities of a coalition. Either that, or they're still pissed because they consider their former boss Lafontaine a traitor. And since he left his new party in 2022, they consider him a traitor as well now.
Which is because Die Linke is of course still associated with the SED's taint, because it can't distance itself from its past as the governing party in a dictatorship. However, nonetheless it has gone from one victory to the next, and it seemed likely it would sit in about all state parliaments – even in conservative Bavaria (where they failed in 2008), but since 2012 they're on the retreat in the west. Its main ideology is mostly still populism and welfare state with little idea how to finance it, though.
There is a number of minor political parties which have no significance on the federal level but which may or may not be important in the parliaments of various German states. Some of these come and go, others persist over long times in the shadows, with sporadic attention from the media. Most of them can be grouped into three categories, however:
In particular the city state of Hamburg seems to be prone to these ones over the years. Examples include the “Grey Panthers”, a party of/by/for retirees. Given that Germany is an overaged society with a lot of retirees, one might expect that they're also a heavy force of voters, but no. A second example was the “STATT Partei”, a populist party with unclear ideological profile - really, us Germans have no idea what they were about except not being the other parties! Another freaky example bordering on right-populist was the so-called “Schill Party”, which was founded by a fired judge who possibly wanted to style himself as Judge Dredd. Anyways, after facing acute incompetence and a cocaine scandal involving the hypocritical “Judge Merciless” as he was called (and liked to style himself), his party kicked him out and faded with him again into insignificance. That's life.
One notable example, especially in regard of the 2009 Bundestag election, would be the so-called Pirate Party, a new party dedicated to the subject of informational self-determination. Seems they petered out, though.
The most recent notable example is “Volt”, a party which is part of pan-European Volt and wants to implement “Best Practices” (urgh, manager jargon) - if some other EU country had success with some politics, why not copy it? They're represented in several communes. Their color is purple.
Finally, there's the Freie Wähler (“free voters”) founded in 2009. You see, Germany has had people for long who wanted to do something for their communities without joining those pesky parties. In many communes, they even have a majority, being especially strong in the South. As they became more popular, they decided to become a real party, which wants to give more power to the communes. Since 2010, they even have an organization on federal level. As mentioned below, they're part of a coalition in Bavaria.
In the post-WWII political climate, right extremist parties are understandably under quite a taboo. Yet, there have always been some parties on the right-extremist spectrum who do creep up in a state parliament now and then, for one legislature period - but usually not for longer, because the levels of incompetence and infighting they show once in parliament are quite staggering. For example, the DVU (Deutsche Volksunion - German People's Union) managed to get elected into state parliaments nine times - and only once the faction didn't split over infighting. And that despite the part being under the rather dictatorial rule of its long-time president and main money giver, a media entrepreneur from Munich. In 2010/11 (after said founder had retreated – in 2013 he died) they decided to join the NPD - except that parts of them weren't happy about it and decided to sue. So, business as usual.
More successful than the DVU, and with a longer history is the NPD (Nationaldemokratische Partei Deutschlands - National Democratic Party of Germany), which oscillates between trying to appear respectably and making contacts with the neonazi skinhead scene. Currently, it very much is the latter, but still (or because of it?) the party was for some time very successful on the state level, if in something of a financial crisis.
The third “big” right-extremist party are the Republikaner (Republicans - no, that is no joke). It is somewhat debatable whether they are right-extremist or merely very conservative and rightwing. They started out as a more conservative CSU splitoff, but during the course of their history had contacts to both NPD and DVU. For some time they appeared to be the biggest and most moderate of the three, but since the early Naughts the NPD seems more successful.
Of course, those parties are all spied on by the Gestapo… Stasi… I mean, the Verfassungsschutz, the German domestic intelligence service. Or rather, all 17 of them - every state has one and the federal level, too. And they all are under the threat of being banned, which can happen to parties here when the Bundestag asks the German Constitutional Court (who in this regard is Germany's IRL equivalent of Ian) to look into the matter. This was tried 2001-03 (yeah, it took that long) with the NPD, the most extreme of the three, but it failed rather spectacularly when it was discovered the party was choke full of Verfassungsschutz agents, so much that the Court saw itself as unable to differentiate what is true party ideology and what influence of the agents!
And then there's the recent AfD. Founded in 2013 by various professors of the economy, they may have started being right-libertarian/conservative/euroskeptical/Christian, but since then, the party has moved further and further to the right, sometimes touching with the German equivalent of the alt-right. To the point that several of their former founders left because this development was too much for their taste. Which included Frauke Petry on the very next day after being elected into the Bundestag in 2017. Because yes, the party is the first party to the right of the Union which made it into the Bundestag since 1957, with a double-digit result to boot. They're especially strong in the former GDR, in some lands even beyond 20%, in parts of Saxony even the strongest one (currently).
The whole party wasn't observed by the Verfassungsschutz until 2022 when they were deemed as suspicious, but some members are.
On a final note, there's the Europäische Arbeiter-Partei (European Labor/Workers' Party - it had a Trotskist bend) / Patrioten für Deutschland (Patriots for Germany) / Bürgerrechtsbewegung Solidarität (Civil Rights Movement Solidarity) or however it's called this decade. See, all of these were/are headed by the same woman, a Helga Zepp-LaRouche. Yes, she's the wife of that LaRouche guy who thinks Elizabeth II was running a drug ring. But hey, they have a great idea how to save the economy: Building a maglev connection from Brest via Berlin to Vladivostok! No, make that a world-spanning network of them!
Officially BTW none of them actually uses brown as their party color. And the fact that the SPD chose umber as their color in a restyling under Schröder doesn't make them one of those.
A footnote, pretty much. Most noteworthy are one of if not the oldest parties of Germany, the Zentrum, which was almost-perpetual government party during the Weimar republic (1918/19 - 1932) and the DSU (Deutsche Soziale Union) which was part of the last Eastern German government and thought about becoming an eastern CSU for a while. Then, there's the BP (Bayernpartei), a seriously secessionist party for, you guessed it, Bavaria. They aren't openly monarchist, even if AH fans would like that, but they have contacts to Wittelsbach fanclubs. Besides, we have the DP (Deutsche Partei – that is, the new-founded version from 1993), the PBC (Partei Bibeltreuer Christen), the AUF (Partei für Arbeit, Umwelt und Familie), the Bündnis C of the latter two, the CM (Christliche Mitte), the Familien-Partei and maybe some we forgot. All of them are or have become hopeless splinter parties, even if the Zentrum is actually represented in the Bundestag again since 2022 when an AfD guy changed camps. The LKR (Liberal-Konservative Reformer) of former AfD boss Bernd Lucke joined them after the European elections in 2019. Same thing applies for Frauke Petry who left the AfD to start her own party, Die Blauen (the blue ones - yes). Jörg Meuthen, another former AfD boss who also quit, hasn't started his own party. Yet. Instead, he joined the Zentrum too, so they're represented in the Euro parliament now as well.
Oh, and there's the ÖDP (Ökologisch-Demokratische Partei – ecologic-democratic party), which was founded in 1982 by similar people as the Greens. However, they also emphasize family, want parents to receive (more) money from the state (“Erziehungsgehalt” – a wage for raising kids), and are especially critical about abortion.
There's also a mix of really, really strange parties that are not too dissimilar from AH.com parties, yet which would never make a stand should they ever get voted into any parliament. Like the Deutsche Sex-Partei (yes, exactly what you think it is), the Anarchistische Pogo-Partei (which suggests dividing Germany into three zones: One for punks like them who live on UBI; one for squares who work and pay taxes to support everything; and one for nazi skins, too brutal policemen, and other violence-loving people, so they can beat the shit out of each other without endangering the other two groups), the really esoteric Naturgesetzpartei and the Beer Drinkers' Union. The P.A.R.T.E.I. is the latest example which even managed to send their boss Martin Sonneborn to the European Parliament, which lacks a 5% (or any) threshold. However, they wouldn't make a stand on AH.com either due to lacking coolness like airships or battleships…
Absolute majorities (a single party receiving a majority of seats) are rare in Germany. Only during 1957-61 the CDU/CSU had this, and even then, Adenauer allowed the small DP to join the government. Usually no single political party manages that, forcing them to create coalitions with other parties. Only ten years ago some coalitions were unthinkable, but nowadays it seems to have become a free-for all… this is where German political colour theory is applicated.
A good overview about the situation in the länder is here on WP.
A coalition between the CDU (or recently the CSU as well) and the FDP, also called a christian-liberal or bourgeois (
bürgerliche) coalition, especially in the times before said colour theory came about. It has been done multiple times on the federal level by Konrad Adenauer (1949-56 and 1961-63, the CDU was running all alone in-between), by Ludwig Erhard (1963-65), running longest under Helmut Kohl (1982-98) and then again by Angela Merkel (2009-13).
Current (April 2022) state governments of that type run in Northrhine-Westphalia, of all places, but now even they lost their majority. Another traditional stronghold of this option, Baden-Württemberg, was lost to Green-Red after the elections got seriously affected by the Fukushima disaster.
Had no official name, although “Tigerenten-Koalition” was suggested (maybe as a joke), and “bee (or wasp) coalition” would also work.
The Grand Coalition (a coalition of the CDU and the SPD) derives its name from the fact that the two biggest parties in Germany form a coalition. Usually that's an emergency measure when no other option is unavailable (like in the current Bundestag, as Die Linke was shunned by all sides, as said), though on some state levels it is a true option of similar ideologies. Germany has been run by grand coalitions three times, once under Kurt-Georg Kiesinger (1966-69) and more recently under Angela Merkel (2005-09 and 2013-21 again). Said coalition under Kiesinger was in fact made to introduce the Notstandsgesetze which were veeery controversial and needed a two-thirds majority to change the constitution.
Current (August 2019) state governments include those of Saarland, Saxony (lead by the CDU), and Mecklenburg-Western Pomerania and Lower Saxony (lead by the SPD).
Increasingly incorrectly named, since in many länder other parties than CDU/CSU and SPD make it to place #2 or even #1 – Greens in Hesse, Baden-Württemberg and Bavaria (where the SPD only made place #5!), Linke in several eastern länder (not counting Berlin), AfD in several other eastern länder, and the negative record would be Thuringia in 2019 where Linke are #1, AfD #2, with the Linke getting more votes than CDU and SPD when put together! – Even in most western länder and on federal level, this coalition doesn't get a two-thirds majority anymore.
The coalition between the SPD and the FDP, also called a social-liberal coalition (again, the common name before colour theory came up). These have been existing sporadically throughout the history of the FRG (notably on the federal level, both the governments of Willy Brandt and Helmut Schmidt have been Red-Yellow coalitions), but following the 'treachery' of 1982 (when the FDP dropped their support for the SPD via a vote of no confidence), the SPD has been more willing to cooperate with the Greens.
A very stable social-liberal coalition existed in Rhineland-Palatinate from 1991 to 2006.
A coalition between the SPD and the Greens. The federal government of chancellor Gerhard Schröder (1998-2005) was a Red-Green one. It's been this coalition that really started the trend of naming coalitions for their parties' colours.
Under opposite premises (“Green-Red”), Baden-Württemberg had this with the first-ever Green minister-president.
A coalition between the SPD and the Linke (or the PDS before them). And, yes, it is really called Red/Red. (Once in the past, some people like the radical Green Jutta Ditfurth used to call the SPD “pink” to express that they're just moderately red, but nowadays pink is rather associated with the gaysexuals, so there's no way to call it “Pink/Red”.) This one is common in various East German states, but is currently considered taboo on the federal level.
Last of them governed Brandenburg. But they lost their majority in September 2019. Returned in Mecklenburg-Vorpommern in 2021.
Analogously a coalition between the SPD, the Greens and the Linke, rarely seen in practice and therefore a rather theoretical idea, though there have been talks about making this after the stalemate in the Hesse elections (which eventually failed and led to premature elections and the resurrection of Roland Koch). Basically the same exotics and taboos of Red/Red alone apply here as well, but the addition of the Greens and their anti-authoritarian background contrasted to the SED background of the Linke makes this alignment even more complicated. A début in Saarland after the 2009 election would have clearly provided a majority for this, but the Greens eventually settled for another début, Jamaica as explained later.
The closest thing to Red-Red-Green ruling a state were the Red-Green minority government in various länder that depended on parliamentary support of Die Linke (starting with Saxony-Anhalt and the then-PDS in 1994, hence called the “Magdeburg Model” after its capital), but since 2014, a certain Bodo Ramelow (first minister president of the Linke) leads an actual coalition like this – except that Die Linke is the strongest partner. Since 2016, Berlin has a genuine Red-Red-Green government, with the SPD leading. In 2019, Bremen followed suit.
Since “Yellow” is “Gelb” in German, you can read this abbreviation as “Two Red, Two G”. Nothing more. Doesn't exist yet and probably never will, Socialist Linke and libertarian FDP simply don't fit together.
This coalition has the same colors like a traffic light in Germany and most of the world. It has been existing on several occasions on state and communal level. It is helped by the fact that both FDP and Greens would form coalitions with the SPD, but hampered by the already mentioned feud between FDP and Greens. Currently, the FDP has excluded any possibility of coalitions with the SPD on the federal level, though.
There've been few coalitions of this type on state level, the post-unification government of Brandenburg (1990-94), Bremen (1991-95) and since 2016 in Rhineland-Palatinate. And on federal level since 2021.
“Senegal coalition” would fit as well, but at that time, coalitions weren't named after countries' flags' colors yet – this was introduced by the coalition below. And “Ampelkoalition” is easier to say anyway.
Named for the colors on the Jamaican flag and the assumed exotics of both Jamaica and said coalition, which was suggested as a possibility in 2005 but dropped in favour of the Grand Coalition. As former Foreign Minister Joschka Fischer commented on this: “Can you imagine Angela Merkel with dreadlocks and smoking pot?”
Of course, it's mainly CDU members who talk about how possible this is, because that would help their party become the governing party. Of course, it was seen unlikely as the Traffic Light (which is the same just with the SPD on top) because the Greens had excluded any possibility of coalitions with the CDU on the federal level. It's made a début with the government of Saarland (2009-12).
Though the term “Jamaica Coalition” can be found in local German newspapers back into the 1990s, the widespread usage of the term first came up with the election night of 2005 when a public broadcasting commentator coined the term seperately. Before that night, the thought-experiment of a Black/Yellow/Green coalition has mostly been labeled with the portmanteau “Schwampel” which derived from “schwarze Ampel” or Black Traffic Light where the red colour of the first light is to be replaced by a black one.
Schleswig-Holstein followed in 2017, and after the federal elections of 2017 there were week-long coalition talks about it until FDP boss Lindner decided to blow them up.
The “Dänen-Ampel” is only possible in Schleswig-Holstein, with its SSW (Südschleswigscher Wählerverband), the party of/by/for the Danish minority. They talked about it in 2005 and 2009 until it worked out 2012-17.
Sometimes also called “Red/Green/Blue” or “Gambia coalition”, but that was before the AfD became strong. Furthermore, the CSU claims blue for themselves as well… it's really getting confusing.
A coalition between the CDU and the Greens. This was unthinkable until very recently. Again, Hesse was the groundbreaker, with a surprisingly very stable coalition on city level being formed in Frankfurt. In 2008, a coalition on state level was formed in Hamburg; it seemed to fall apart about the matter of secret deals not revealed to the respective party bases only five months after the election and eventually did so when, after a referendum crushed plans for more comprehensive education (no matter how it had ended), Governing Mayor Ole von Beust as the staple that held Black-Green together retreated from the political scene. Premature elections came in February 2011 and led to an absolute SPD majority.
Max Sinister once (when it didn't exist yet) thought about naming it derogatorily “Swamp coalition” but never told anyone. Until now.
Current (August 2019) state governments of that type run in Hesse and, under opposite premises (“Green-Black”), in Baden-Württemberg.
Existed in the early years of West Germany in some lands (Berlin, Bremen, Saarland). Last ones of them died in 1959, until they were resurrected in 2021 in Saxony-Anhalt.
Believe it or not, but since 2016, Saxony-Anhalt actually has this. After the radical right AfD and the Linke had become too strong, this was pretty much the only viable alternative left. In October 2019, Brandenburg and Saxony will get it too, as it seems.
Consisting of CSU and Freie Wähler. Currently (August 2019) in power in Bavaria, where else. Not to be confused with a coalition of the Austrian ÖVP (pre-Kurz) and Jörg Haider's right-populist BZÖ which was orange too. – The Pirate Party uses orange as well, it really gets confusing…
SPD, Greens and Pirate Party. Only exists in municipalities, as in Bielefeld (which doesn't exist!) and for a short time in Cologne.
Hasn't happened yet (shortly after WW2, some lands had all-party coalitions, but the Greens were only founded in the late 1970s), but was talked about because it might become the only democratic option that has a majority after the elections in Thuringia in October 2019. Then the election happened, and even this weird coalition has no majority. So cooperation between Dark-Red and Black will have to be thought of. Because the alternatives would be worse…
As in, CDU and Linke. Doesn't exist yet, except maybe in some obscure eastern German municipalities, but since the Thuringia elections of 2019 this is one of the only coalitions with a majority there.
Greens and FDP. See, the second FDP color is blue, traditionally. Doesn't exist yet either, but since Kretschmann's Grüne in Baden-Württemberg have ~30% and the FDP there isn't too weak either, it might become possible in the future.
SPD, Greens, (maybe) Socialists, and Volt. “Weintrauben-Koalition” in German. Actually was formed in Bonn.
Or “Haselnuss-Koalition” in German. Named after a song “Schwarzbraun ist die Haselnuß”. A coalition of the one or other Union party with the radical right didn't actually happen yet, although people speculate about it. Closest thing would be the coalition of Union and Deutsche Partei which ended in 1960.
Hypothetical coalition of CDU/CSU, FDP and AfD. Not done yet, the AfD's still considered too far right.