The super-strong Captain Nazi was genetically altered by his scientist father, and developed into the "perfect specimen" in order to fight for Adolf Hitler and the Axis Powers during World War II. Nazi first appeared in Master Comics #21 (December 1941), in opposition to both Captain Marvel and Bulletman. During the second half of his battle with Marvel in Whiz Comics #25 (published the same month), Nazi attacks two innocent bystanders who happened to be fishing near the scene of the battle, after they pull him out of the lake. One of them, an old man named Jacob Freeman, is killed, but the old man's teenage grandson, Freddy Freeman, is saved by Captain Marvel and becomes Captain Marvel, Jr.
Junior, crippled in his Freddy Freeman form by the attack, continues to hold a vendetta against Nazi, and the two frequently battle one another. Nazi also serves as a member of Mister Mind's Monster Society of Evil during the WWII years, before making his final Fawcett Comics appearance in Captain Marvel, Jr. #14 in 1944.
Captain Nazi appeared only sporadically in DC Comics' 1970s/1980s revival of the Marvel Family characters under the title Shazam!, save for reprints of the original Fawcett stories. Nazi's first appearance in a new DC Comics story was in Shazam! #34 (March- April 1978).
Following writer Roy Thomas and artist Tom Mandrake's new interpretation of the Captain Marvel mythos in the 1987 four-issue miniseries Shazam: The New Beginning, Captain Nazi was re-introduced in a 1988 four-part story in Action Comics Weekly #s 623-626. Captain Nazi himself, however, only appeared in #s 624-626. The story was written by Thomas and his wife Dann Thomas, with art by Rick Stasi and Rick Magyar. The new Captain Nazi is a young Neo-Nazi named Lester Abernathy. Abernathy is given his "Captain Nazi" powers, costume and codename by a Neo-Nazi organization called the Sons of Valhalla and battles Captain Marvel. This version of the character made no further appearances and was subsequently retconned out of existence by the 1994 The Power of Shazam! graphic novel, which again altered Captain Marvel's background and continuity.
Captain Nazi was introduced into the modern DC Universe in Jerry Ordway's The Power of Shazam! series in 1995. In the modern series, Nazi had been active during the 1940s, battling WWII-era heroes such as Bulletman, Minute-Man, and Spy Smasher, but placed himself in suspended animation so that he could emerge in modern society and revive the Third Reich. Nazi's brother, scientist Wolf Krieger, and his granddaughter, a super-powered villainess named Madame Libertine who possesses mind-controlling powers, carry on Nazi's legacy in the 1990s and resurrect their hero from his suspended animation chamber in Power of Shazam! #5.
Issues #6–8 of the Power of Shazam series retell the story of Nazi's murder of Freddy's grandfather, his crippling of Freddy, and Freddy's emergence as Marvel, Jr. and attempted revenge on Nazi. After the Marvel Family captures and defeats Nazi, he is sent to Europe to be tried for war crimes committed during World War II.
Captain Nazi eventually joins Lex Luthor's new Secret Society of Super Villains as seen in the miniseries Villains United, where he works with them to torture the Secret Six. He is blinded during the escape of the Secret Six when Catman plunges syringes into his eyes.
Captain Nazi meets his apparent end in Batman #647 while fighting Batman and the Red Hood. The Captain, now sporting cybernetic eyes following his injury in Villains United, has been lent out to the villain Black Mask to assassinate the Red Hood alongside follow Society members Deathstroke and the Hyena. During the fight, the Red Hood apparently kills Captain Nazi by jamming a taser-like weapon into his cybernetic eyes (the only vulnerable part of his body). In Villains United Special #1 however, it is revealed that Nazi has survived. At the behest of the Society, Nazi appeared in Kahndaq to release all of the captives in its prisons and fights Khandaq's ruler and former Secret Society member, Black Adam. During the battle, Black Adam confronts Nazi about how he seemingly survived being killed, at which time Captain Nazi cryptically proclaims that previous origins about him were wrong and that the villain isn't even human; that he is the living avatar of National Socialism given physical form and that so long as there are Nazis in existence, he will exist. Despite this claim, Black Adam easily defeats Captain Nazi.
He has since appeared as leader of a Nazi-themed team in Justice Society of America named "The Fourth Reich" after the "One Year Later" jump, and is an opponent of Wonder Woman in 'The Circle', sporting a generic black costume.
In an episode of Justice League Unlimited, Captain Nazi made a round-about appearance. During a flashback sequence, a character who looks very similar to Captain Nazi is prevented from taking a super-soldier serum by Fawcett Comics hero Spy Smasher. It is later revealed that the serum was created for "Project Captain Nazi." General Wade Eiling broke into Cadmus Labs and injected himself with the mutated serum. He then went on a rampage against the Justice League. The idea of a super-soldier serum in a WWII-era setting is very similar to the premise of Captain America.