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Nazi Anime
Nazis are terrible.
It's unbelievable that even needs to be said. The evil of the Nazi regime should be obvious to everyone. In the 70-odd years since World War II, the Nazis have become Western culture's go-to example of real-world evil. Yet the dangers of hatred and bigotry have persisted, and a quick glance at the news will show more and more people are flaunting their hateful beliefs. So as the dangers of Nazism, fascism, and white supremacy threaten inclusivity, fairness, and democracy, let us repeat: Nazis are terrible.
Where evil exists, however, good people will always rise up and resist. We honor the Allied soldiers who fought in World War II, and in our fiction we find catharsis in the adventures of Captain America, Indiana Jones, and other characters who fight Nazis. For your catharsis, here are recommendations of 10 anime and manga about awesome people (and vampires, and robots...) who fight Nazis.
Hellsing Ultimate
So who would be the anime equivalent to Indiana Jones, the best known fictional Nazi fighter? The most obvious answer that springs to mind is Alucard, the world's most powerful vampire and number one enemy of the Millenium Neo-Nazi organization. The Hellsing Organization's battles against the Millenium's Nazi vampire cyborgs and assorted crazy enemies are super-violent and super-cathartic.
Fullmetal Alchemist: The Conqueror of Shaballa
The parallels between Amestris and pre-Nazi Germany were made explicit in the 2003 anime's ending, in which Edward Elric crossed the gate to our universe. The movie sequel has the Elric brothers taking on the Thule Society, the occultic group that originally backed Adolf Hitler and started the Nazi Party.
Dragon Ball Z: Fusion Reborn
Adolf Hitler himself (referred to as "simply the dictator") appears as a minor villain in the 12th Dragon Ball Z movie, rising from Hell with an army before being swiftly defeated by Gotenks. He's portrayed as a comedic caricature, akin to parodies found in the Looney Tunes or Charlie Chaplin's The Great Dictator.
Black Lagoon
The Black Lagoon crew fights off a more realistic group of modern neo-Nazis in one of the anime's early story arcs. This series deserves extra credit for having black and Jewish characters fighting against Nazis.
Monster
Johan, the main villain in Monster, was bred in a eugenics program, taken in by a Neo-Nazi group as a child and trained to become a supersoldier. Many of the Neo-Nazis think Johan could be the next Hitler. Turns out Johan's even more psychopathic, willing to kill anyone regardless of ideology.
The Legend of Koizumi
How would you kill Hitler if you got the chance? A game of Mahjong? Maybe not the first thing that comes to mind, but in the political-leaders-Mahjong-battling Legend of Koizumi (adapted into a 3 episode OVA) it's the most effective strategy when Hitler and his Nazi cohorts return to Earth from outer space (this is a weird manga, if you couldn't tell).
Spriggan
The anime film doesn't cover the Nazi-fighting arc, but this politically involved sci-fi manga features yet another "Fourth Reich" as antagonists, including a clone of Adolf Hitler with multiple personalites.
Mazinger Z
So far in this list, we've discussed anime characters fighting German Nazis, neo-Nazis, and space Nazis, but have you ever seen giant super-robots fighting a decapitated Nazi? If you haven't but you want to, Go Nagai's old school mecha classic might be right up your alley.
Lupin III
Lupin has fought Nazis many times throughout his franchise's long history, from the 1977 episode "To Be or Nazi Be" to the 1995 special The Pursuit of Harimao's Treasure to even fighting a Nazi version of himself in the 2008 Red Vs. Green OVA.
Mobile Suit Gundam
https://www.youtube.com/watch?v=tlJ5j-hSUmQ
So technically Gihren Zabi never calls himself a Nazi. He's just a totalitarian who wants to kill all those he sees as genetically inferior and sees being compared to Hitler as a compliment. So yeah, he's totally a Nazi. A Nazi by any other name smells just as rotten. Something to be extra vigilant about these days...