This isn't a complete list. The only real figure missing is Vandal Savage, who can take over in at least one event, however since the number of images caps off at 10 I chose to exclude him from this list. Plus he doesn't replace a specific historical figure.
Political leaders:
Adolf Hitler-Adenoid Hynkel(The Great Dictator)
Our swap out for Hitler. Hynkel was born in 1888 as Adenoid Shickelgruber before changing his name. Due to the machinations of the cult of Oliver Haddo, known as the Seven, he was conceived on the nigh of the first Jack the Ripper murder. The ritual led to a being known as the Broodseven-Sub-Two-Raksha entering his body. As a child a time traveller abducted him and leaped into a rival. However, the nanny stole an infant from a poor jewish woman and passed it off as the real Adenoid before his parents returned. Hynkel, as a youth wanted to be a painter but was turned down many times. A friend of his, Jenny Sparks, suggested he try going into politics. After serving in World War I, Hynkel joined the Nazi party, which had been infiltrated by the Brotherhood of the Lamb, of which two of Hynkel's lieutenants, Kemmler and Garbitch, were members. Hynkel would seize power along with other workers following the 1927 Metropolis uprisings and he would rise to replace party leader Freder Frederson as "The Fooey" in 1934. Hynkel's rise to power is said to be incluenced by the Broodseven-Sub-Two-Raksha and the use of a microphone which was actually an SCP that allowed the speaker's voice to control those listening to it.
Canonically, Hynkel allies himself with Benzino Napaloni of Italy and Emperor Yoshiro of Japan. He has various ploys, including an effort to place Aviator Ted Scott in power in the US. In 1939, he invaded Arztozka, starting World War II. He also made a pact with Fearless Leader of the Soviet Union. In 1940, Hynkel was briefly replaced by a jewish look alike, buying time for many to escape his wrath, including the Von Tapp family. Hynkel as the war raged on became more and more paranoid, relying on secret projects like the Ubersoldier program, summoning saxon warlord Heinrich I, searches for the Ark of the Covenant and the Holy Grail, Nuclear Bomb technology from Ixania, and the extermination of Concentration Camp prisoners to fuel a ritual to mind control the Norse Pantheon. Hynkel has shurgged off many assassination attempts such as Operation: Valkyrie and one which appeared to succeed by the Inglorious Basterds destroying a theatre playing the Propaganda film Nation's Pride.
It is unclear how Hynkel died. He is said to have retreated to a bunker, and gone insane, ranting about strange things which he'd viewed from the future. He is also believed to have retreated to Mandoras with other Nazis. American Sergeant Frank Rock, and the vigilante Batman are said to have tracked him down. He is also alleged to have waged a secret occult war until his death at the hands of Hellboy in 1952. Some accounts say his brain was saved, or that he acted as a supervillain leading the Knights of Nordica under the name "The Hate Monger" until his death. These accounts may have some truth to them as Dieter Vogel was revealed to have been cloning Hynkel until this was stopped in 1975. It is generally believed Hynkel died by at least 1974 as the Broodseven-Sub Two-Raksha had left his body by then and did not inhabit a clone.
Hynkel's influence is still felt today. The 1968 broadway smash hit
Springtime for Hynkel became a success despite its subject matter. In 2003, German Chancellor Martin Shormann let in six million jews back into Germany to make up for the Holocaust committed by Hynkel, and in 2011, Hynkel somehow returned to life and attempted to become the leader of the European Union.
Heinrich Himmler-Heinrich Kemmler(The Dresden Files)
Kemmler is a very powerful sorcerer. Something taken from both the Dresden Files and Warhammer 40k(which features necromancer named Kemmler, though that would be a future setting here). Kemmler here was finally defeated by a massive magical army in 1961 with a group consisting of Albus Dumbledore, Yen Sid, Prospero, the Watcher's Council, Hellboy, the SCP Foundation, the White Council and others. This is due to The Dresden Files making it clear that he is one of the most powerful Necromancers of all time and so it would understandably take a lot of power to take him down. Fortunately in this altered setting he is not nearly as powerful yet, allowing him to be killed just a bit easier. Though it should be fun to give flavoring to texts in which he is supposedly assassinated by making it ridiculous or epic, such as having him be sent to another dimension, defeated by several powerful wizards, and enchanted weapon and so on.
Herman Goring-Hermann Herring(The Great Dictator)
Not much to say as he has a brief appearance. We can assume he is simply Goring under a different name.
Konrad Adenauer-Colonel Wilhelm Klink(Hogan’s Heroes)
As mentioned before the idea of making Klink the democratic leader comes from a way to justify how Klink is portrayed in crossovers, such as his cameo in the 66' Batman series and The Simpsons were Homer has been sending him letters. Therefore he took a "Know nothing" approach.
Wilhelm Pieck-Freder Frederson(Metropolis)
Frederson is from Fritz Lang's Metropolis. His inclusion makes that film's ending a Pyrhic Victory. In the film, he is a member of the upper Class, the son of the the City's master Joh Frederson. He lives a hedonistic life until he sees the struggling poor workers and falls in love with one of them, a girl named Maria. After sneaking below in disguise and taking the place of a worker. Their cause becomes his cause. However, the film implies he will serve as a mediator to the government and the workers. In Universe, his backstory is both an advantage and a disadvantage. He was born a member of the wealthy class, so he is criticized for this, but at the same time he has also worked alongside the working class. Here he is roped into the Communist side due to his Pro Worker's affiliation. He has been removed from power by Hynkel's rise as the new leader of the Worker's party, now the Nazi party and seeks to reclaim his old position as he does not trust Hynkel.
August Von Mackensen-Baron Munchausen(The Adventures of Baron Munchausen)
Baron Munchausen, based on the exaggerated tall tales of a real figure's military service during the Russo-Turkish War, the fictional Munchausen has ridden on a flying cannonball, travelled to the Moon, and been swallowed by Sea Monsters multiple times. He has also in one account been granted immortality, as well as being known to have cheated death multiple times. He even according to one account encountered an Astronaut on the Moon. However immortal he may be, it's possible, for someone in search of him, to find him, and recruit his help in overthrowing Hynkel. Should he succeed, he's unlikely to remain in power and would sooner give it up to go on more adventures. Munchausen was chosen because Mackensen has a type of "Awesome meme presence" with his Prussian outfit, distinctive hat, and mustache. Munchausen is the closest fictional character I could think of. He's an old Prussian(even more so since he's hundreds of years old). Has a nice hat, a moustache, and does insane things all the time.
Wilhelm II-The Inca of Perusalem(The Inca of Perusalem).
in 1901, Germany attempted to invade the United States. Despite the death of President Henry Fleming and assumption of the Presidency by John Norton, Germany was defeated and in the aftermath, the Kaiser was removed from power, replaced with Wilhelm III as a puppet ruler. No one quite knows what became of Wilhelm II after he lost his position, but it seems that he travelled to the nation of Parador and to the long standing Incan civilization. Possibly given into madness, he returned as the self proclaimed Inca of Perusalem. Remaining a powerful figure, Wilhelm II may just make his long awaited comeback.
Wilhelm III-Friedrich I(Southern Victory)
The former Puppet Kaiser, Wilhelm III is now in the same boat as his father. However, he intends to mount a return to power. While he originally wished to take the name of Wilhelm III like his father, the perceived shame to the family has changed his mind. He now wishes to be known as Friedrich I. This is likely due to Frederick the Great having an unknown stand in replacing him. Because Wilhelm III lacks. much Fictional presence, fantasy casting, specifically Ian McKellen's Richard III, which shifts the Shakespeare play to 1930's Fascist Britain with Nazi iconography,is used here. It's another "Third" and evokes his "German Puppet King" status.
Victoria-Schneewitchen(Snow White)
The daughter of Queen Victoria and the Princess of Germany. While she would have been named after her mother, instead she was named after a Medieval Princess famous for being placed under a curse and awoken by the kiss of a Prince. She is quite popular in Germany and even Hynkel is a fan of her, often seen drawing her during meetings. Also I think she should be included for the Joke value alone. Who wouldn't want to be able to say, they won World War II as Snow White?
Günther von Kluge-Johann Schmidt(Marvel Comics)
Schmidt was a bellhop in a hotel when Hynkel visited and vowed to turn a random employee into the greatest weapon the Nazis had, dissatisfied with the then current efforts of Nazi scientists to create super soldiers. As it happens Schmidt was a very dangerous man. His face transformed by an experimental super soldier serum created by Dr.Abraham Erskine. Schmidt now plans to overthrow Hynkel. In the Canon, Schmidt follows his MCU counterpart a bit more closely than his comic. counterpart.