A whole bunch of stuff:
Knights of the Charter: A successful Chartist revolution in 1839 galvanises the radical liberals and early socialists in Britain. When 1848 breaks out Britain enthusiastically backs the revolutionaries resulting in successful revolutions in the low-countries and western Germany. Featuring Ashanti Princes in the Netherlands working with the British, Dutch and Garibaldi to export the revolutions to their homelands, the averting of the Great Famine due to David Owen's agricultural collectivisation program and the American Civil War escalating into a global conflict that destroys the French Empire and leaves the world divided between the Alliance of Free States and the Reactionary Habsburg-Romanov alliance of the Russian Empire and restored Holy Roman Empire.
Britannia Rules the World: An over-the-top dystopian timeline that's intended to critique and deconstruct Brit wanks. ITTL the British are able to peacefully resolve the issues with their American colonies and grant them representation averting the American Revolution. As a result, slavery becomes deeply entrenched in British politics and the resources of the Empire are thrown behind supporting the expansionist aspirations of the colonies. Marriage alliances result in the United Kingdom of the Netherlands (including Belgium and Luxembourg), Denmark-Norway and Prussia all being incorporated into personal unions with the UK. The Hanoverian Empire steadily transforms into a repressive militarised slavocracy, who make the Draka look like a bunch of hippies, which dominates the world with their equally reprehensible Portuguese allies.
Liberty and the Lash: A dystopian timeline where Slave Power wins out in the US and Liberalism never embraces Abolitionism. No single PoD as it's more of a "what needs to happen to achieve this end goal" sort of timeline but various notable things include: the legalisation of slavery in the Indiana Territory resulting in Indiana and Illinois becoming Slave States, no Trail of Tears meaning that more southern slave owners move to the territories, Ernest Augustus coming to the British throne in the late 1820s and intervening in the Belgian Revolution which forces Britain to remain focused on European affairs and undermines its efforts to oppose the international slave trade, the rise of a horrific trans-Pacific slave trade, liberal revolutions in the Netherlands and South Africa that enshrine the right to own slaves as a part of the fundamental right to property, the horrors of the Scramble for Africa being carried out by empires that both maintain and actively encourage the slave trade and Liberia becoming a major hub in the re-energised trans-Atlantic slave trade.
Iranian Knights: A Sassanid timeline where Kawus succeeds Kavad instead of Khosrow. Using Mazdakism, which he is the dominant authority on following Mazdak's martyrdom, Kawus is able to carry out far more extensive reforms than Khosrow did IOTL which, despite initial instability, leaves the Sassanid Empire in a much stronger state in the long run. The Byzantines aren't so lucky with Justinian dying of plague and getting caught up in several devastating civil wars with Kawus and his successors taking full advantage of the situation, ultimately subsuming the ERE and weathering the storm of the Arab conquests (under a very-different Zoroastrian-influenced alt-Islam). The Iranian Empire steadily transforms towards a centralised semi-secular bureaucratic empire, along the lines of China, with religious authority steadily giving way to bureaucratic legitimacy and Zoroastrianism evolving in a more transtheistic and inclusive direction.
Broken Cross: A Christendom screw. Been done better elsewhere. Featuring Muslim Southern Europe, a big-dick Saxon Empire that unites the various cultures and faiths of the Baltic into a cohesive state and conquers northern France and Vikings up the wazoo.
Sons of Abraham: A pan-Abrahamic timeline where the barriers between the Christian and Muslim worlds are a lot more blurred during the Middle Ages, Islam is regarded as being as much a part of Europe as Christianity and Judaism and all three Abrahamic faiths coexist with even the most Christian countries having significant Jewish and Muslim minorities. Featuring: Hellenised Muslim Byzantine Abbasids, multifaith Aquitaine founded by Odo the Great and Munuza, Jewish Hungary and Novgorod, the Crusades inadvertently becoming a multifaith coalition and the Kingdom of Jerusalem being established to safeguard religious liberty in the holy land, the Nicean Church shattering into a dozen schismatic sects, several rival Caliphates in both Sunni and Shia flavours (as well as a bunch of strong independent Emirs who don't need no Caliph), Amazigh mercenaries becoming a standard feature of European warfare, Amazigh mercenaries playing a key role in the Norman conquest and being settled in northern England following the Harrying of the North and the peoples of the Abrahamic faiths learn to put aside their differences, live in peace with each other and team up to dick on the pagans.
Broken Chains: Due to the Romans being bogged down by a worse Numantian War, the army led by Consul Repilius being wiped out in a freak storm and various rebellions in Greece, Italy and North Africa managing to gain traction the First Servile War results in the rebels forcing the Romans to come to terms after cutting off grain supplies from Sicily and North Africa. The leader of the revolt Eunus, styling himself King Antiochus of Sicily, establishes a new religion with a strong emancipatory message to legitimise his rule and rally the slaves and dispossessed to his cause whilst Tiberius Gracchus, who had been taken prisoner and comes to sympathise with the rebels, becomes a St. Paul figure helping to spread the faith to the Roman masses in concert with his populist political career. As the Roman Republic steadily collapses due to external invasions and internal strife Sicily comes to take it's place as the hegemon of the Mediterranean and spreads it's emancipatory faith across the known world and seeking to liberate the enslaved and oppressed throughout the world.
For Want of a Thunderbolt: Seleucus Nicator survives his assassination, secures Thrace, Macedonia and Greece and stabilise his Empire in Anatolia. His son finishes off the job of reuniting Alexander's Empire after invading Egypt and beating off the Gallic Invasion of Greece. From there the history of the classical era diverges extremely from IOTL. Featuring Hellenophobic Rome that's BFFs with Carthage, Indianised Arabia, Caucasian Galatia, the emergence of an Greco-Indo-Iranian cultural melange throughout the Empire of Asia, pre-Bantu East African civilisations, all of the religions claiming Zalmoxis, Rome getting the Jerusalem treatment and the diaspora resettling in Spain under Carthaginian protection, Carthage circumnavigating Africa and discovering the New World in the 7th century, Buddhist Gaul, the Republic of Israel during the Second Shofet Period, Samaritans forming an Empire in the levant, an atheistic-materialist philosophical and political movement gaining traction, Buddhist Gaul, Hindu Magyar Iran, multiple dynasties claiming the mantle of the Asian Empire of Seleucus, Alexander and the Achaemenids, Jews for days in a wide variety of flavours and long-term cultural and economic consequences of extensive contact between China, India and the Mediterranean.
The Legacy of 1830: The Revolutions of 1830 escalate into a global war lasting 4-5ish years. This completely throws off the trajectory of the following century from IOTL. Muhammed Ali has a completely free hand in his war with the Ottomans laying the foundations for a united Arabian Empire that will become a superpower, French Algeria is strangled in its crib and European colonialism is kept out of North Africa entirely, Russia is completely expelled from the Caucuses, Britain ends up going through several revolutions and retreats from global colonialism, Jamaica becomes a second Haiti, the US absorbs Canada turbocharging its expansionism, Prussia gets screwed, Austria gets wanked, Franco-Spanish-Sicilian Bourbon Alliance dominated Western Europe, France annexes Flanders and Wallonia, South Africa declares independence, revival of the Anglo-Moroccan Alliance and Sweden can into Finland. And these are just the immediate consequences. Later on a successful Indian Mutiny restores the Mughal Empire with French and Arabian support, rapid overextension causes the US to collapse in the wake of multiple uprisings and secession crises and it is generally agreed that Europe ends at the Sahara.
The Time of Monsters: The US enters WW1 6-12 months earlier and the Bolsheviks still take power in Russia. As a result, Germany is in a weaker position and the Bolsheviks string out the Brest-Litovsk negotiations long enough for Germany to be on the brink of collapse before talks collapse and they re-enter the war. The Soviets have a seat at Versailles but, as the post-war revolutionary wave starts to erupt, they walk out denouncing the talks as an Imperialist land-grab (which isn't entirely untrue) and declaring the commencement of the world revolution. WW1 resumes until 1922 when exhaustion, disease and the withdrawal of the US following Wilson's crushing defeat in 1920 trying to run for a third term forces the combatants to sign an armistice when it becomes clear that neither side can break the stalemate. Peace is declared, though none expect it to last, and Eurasia is divided between the nascent Soviet World Republic that stretches all the way to the Netherlands and the Concert of Eurasia that was established to contain them. But within the Concert all is not well. The French-led Integralist Bloc dominates Catholic Europe, much to the chagrin of their British allies under an increasingly autocratic permanent National Government, and Integralism is fast becoming the dominant tendency of political Catholicism. Across Africa and Asia the colonised peoples are beginning to stir, sensing the fragility of their overlords, whilst the non-European Empires plot to betray their erstwhile allies and claim their place in the sun. And in America the Republic shambles from disaster to disaster as the Democratic Party falls increasingly under the influence of the KKK, rapidly growing in influence due to the perceived threats of "Jewish Communism", "Catholic Integralism" and "Gerveyite Negro Supremacism", while the Republicans, deeply mired in corruption, horribly mismanage the Great Depression throwing millions of Americans into desperation and poverty. From out of the chaos one man has emerged to forge a coalition of radicals from across the political spectrum to deliver the program that will save America and share its bountiful wealth with all its citizens; Huey Long, the last hope for democracy. The old world is dying, the new world cannot be born and now is the time of monsters.
Century of the Common Man: A successful Operation Long Drop kills everyone at the Tehran Conference. As a result, the post-war leadership of the UK (Stafford Cripps), USA (Henry Wallace) and the USSR (Anastas Mikoyan) are all considerably more cooperative and are willing to pursue (mostly) good faith attempts to build a lasting peace and usher in a new era of global cooperation. As a result, the Cold War is completely averted. European politics is dominated by an alliance of Communists and Democratic Socialists, the USSR enters the postwar era utterly secure and fully embracing reforms and the US undertakes a massive expansion of the welfare state. Though things are far from perfect by and large the world enters a new era of unprecedented peace and prosperity with the dawning of the Century of the Common Man. What follows would be an exploration of the political and cultural consequences of a world without the Cold War with one of the main framing devices being the intergenerational stories of three soldiers (one British, one American and one Soviet) who meet during the joint occupation of Germany and their descendants.
A History of the American Social Democracy: The 1848 Revolutions are larger and more devastating yet still end in defeat. With Britain no longer a safe haven for would be revolutionaries, due to a civil war sparked by a Chartist Uprising, thousands more radical emigres move to the United States, including a young Karl Marx and Friedrich Engels. This larger pool of radical intelligentsia and exiled radicals, along with native radicals like Horace Greeley and William Lloyd Garrison, decide to establish the foundations for an independent party that will mobilise the growing industrial proletariat in the pursuit of socialism and the transcendence of capitalism. From humble beginnings the Socialist Workers Party of America would grow from rivals to the Free Soil and later Republican Parties to being part of the Union's wartime coalition during the Civil War. Growing rapidly during America's post-war industrialisation and the rising labour radicalism that came with it and absorbing the Radical Republicans following the betrayal of Reconstruction they edge out the Democrats in the northern cities and establish themselves as the main opposition party in the border states. During the 1880s and 90s they breakout and establish their hegemony over the American political system through exploiting the division between the Republican and Democratic Parties, absorbing the agrarian Populists and pursuing extensive political and electoral reforms that radically reshapes the very character of the American body politic. The Gilded Age is stillborn and the age of the American Social Democracy reigns supreme.
A History of a Land and its Peoples: Some musings on Binational Palestine and successful pan-Arabism.
Ruins of a Global Political System: Currently planning to make this one work but I'll leave it in just in case. A worse 9/11 results in Joe Biden establishing a bi-partisan National Unity Administration that takes the place of the Bush years and leaves the entire American political establishment utterly discredited and holding the ball when the 2008 Financial Crash hits just as political polarisation is on the rise. In 2008 America elected the sort of black radical extremist socialist that Fox News claimed that Obama was just in time for the Arab Spring. Heavily inspired by Ruins of a Global Political System and covers many similar themes.
In addition I also have 2 Warhammer 40K timeline ideas.
The first is a straightforward alternate history timeline where Ferrus Manus kills Fulgrim during the Dropsite Massacre. The Horus Heresy plays out as IOTL but after the war Ferrus Manus throws his support behind Rogal Dorn against Robute Guilleman. This significantly alters the trajectory of the 40k timeline and results in an Imperium with a more pan-Asian aesthetic. The Imperium, or Dai Man as it is come to be known, evolves into a centralised Confuscian-style Bureaucracy instead of the heavily decentralised theocracy of IOTL and as of the 41st Millennium is going through a multi-faction civil war following the expulsion of the Fang Dynasty (Qing analogue descendants of the Space Wolves and White Scars) and the Wars of Humiliation against the Gweilo. This timeline features not-Japan Ultima (known as Uroshima ITTL due to linguistic divergences), the Kroot as the not-American rising power of the Eastern Fringes, Alien Megacorporations seeking to plunder the wealth of Dai Man and flood their worlds with Drukhari narcotics, Warp Canals, Bureaucrats, Pirate Queens and the evolution of civilised Orkoids following the War of the Beast playing out very differently.
The second one is pure crossover crack fic where each of the Primarchs is raised by characters from various fictional settings (cannons adjusted accordingly to fit in the 40k setting). The current plan for the Primarchs is thus:
- Lion El'Jonson found and raised by the crew of Serenity (Firefly), named Lionel Tam. Legion called Lionel’s Raiders A.K.A The Browncoats. Space cowboy! Falls to Chaos. Is killed after the Heresy.
- Fulgrim found and raised by Kamina (Gurren Lagann), actually is Simon. Legion named the Dai Gurren Legion A.K.A. the Spiral Lords. Falls to Chaos (Tzeench) and becomes a Daemon Prince
- Perturabo found and raised by Baron Wulfenbach (Girl Genius), named Peter Heterodyne-Wulfenbach von Europa. Legion named the Jaegermarines. Falls to Chaos and becomes a Daemon Prince.
- Jagatai Khan found and raised by Cimmerians on Hyboria. Named Conan (Conan). Falls to Chaos (Khorne) and becomes a Daemon Prince.
- Leman Russ found and raised by Angel (Buffy and Angel), is Connor. Forced to kill Angel after he goes Angelus. Legion named the Knights of Midnight. Falls to Chaos and becomes a Daemon Prince.
- Rogal Dorn found and raised by Fire Lord Zuko (Avatar), named Ruko. Legion called the White Lotuses. Loyalist.
- Konrad Curze found and raised by the Judges of Mega-City One (Judge Dredd), named Fargo Dredd. Legion named the Lawbringers. Loyalist. Founds the Adeptus Arbites ITTL.
- Sanguinius found and raised by Darkseid (DC), named Samael. Legion called the Exterminating Angels. Loyalist, but has own agenda.
- Ferrus Manus found and raised by John Connor (Terminator), named Kyle “Iron Fist” Connor. Legion named the Fatemakers. Falls to Chaos (Nurgle) and becomes a Daemon Prince
- Angron found and raised by Angus McFife XII and becomes Angus Mc Fife XIII (Gloryhammer). Legion called the Space Knights of Crail. Loyalist.
- Roboute Guilliman found and raised by Eric von Shrakenburg (Draka), named Rudolf von Shrakenburg. Falls to Chaos (Slannesh) and becomes a Daemon Prince. Legion named the Praetorians.
- Mortarion found and raised by the last remaining Green Lantern in the galaxy. Legion called the Iron Wills.
- Magnus the Red lands on Telguuth (Tales of Telguuth) and is raised by sorcerers. Is names Tesro Karnik/Yazella (has their soul merged with a mortal women’s after his body is destroyed yes that is in the source material). Joins the Heresy in an attempt to betray the Chaos Gods and bind them to his will using the Webway. It doesn’t work and he gets possessed by many daemons. Later he is able to overcome his possession for a brief moment in order to backstab the forces of Chaos, sacrificing himself in the process. Legion called the Witch Lords.
- Horus Lupercal found and raised by John Luc Picard (Star Trek), and named Horatio Jean-Paul Picard. Legion named the Intrepid Voyagers.
- Lorgar found and raised by Quinn Dexter (Night’s Dawn Trilogy) on Catachan, named Iblis Levi. Legion called the Lightbringers A.K.A. the Luciferii.
- Vulkan found and raised by Katisa and the Ilyassai (Imaro), named Imaro. Legion called the Imperial Lions.
- Corax found and raised by Andrew Ryan (Bioshock), named John Galt. Legion called the Living. Falls to Chaos. Buddies up with the Ferengi.
- Alpharius and Omegon found and raised by the crew of Red Dwarf (Red Dwarf), named Jim and Bexley. Legion called the Boys from the Dwarf. One falls to Chaos and the other remains loyal, but it is later revealed that the Chaos one was loyal the whole time and betrays the forces of Chaos.