Baron Zemo

Baron Zemo is the name of two fictional characters, both supervillains, in various Marvel Comics comic books, notably Captain America and the Avengers. The original Baron Zemo was created by Stan Lee and Jack Kirby and was first seen in a flashback in The Avengers #4 (March 1964), though he did not actually appear in person and was not identified by name until The Avengers #6 (July 1964); the second first appeared in Captain America #168.

Baron Heinrich Zemo

Dr. Heinrich Zemo, 12th Baron Zemo was one the top scientists in the Nazi Party who fought Captain America and his allies during World War II. Zemo dressed in a red costume with a hooded mask. Zemo created many weapons, including a death ray, a disintegration pistol that was a miniaturized version of his death ray, primitive androids, and the so-called "Adhesive X", an adhesive that could not be removed by any known process (until years after Zemo's death, when the adhesive-using villain called Paste-Pot Pete found a way to reverse it). While in battle with Captain America, a vial of Adhesive X was shattered onto his mask; the adhesive poured inside it and permanently attached the mask to his face. Although Zemo could still see through the eyeholes and hear, speak and breath through the mask's thin fabric, he could no longer use his mouth to eat and had to be fed intravenously. Zemo was driven insane by this disfigurement. (Apparently the Nazis never considered simply destroying the mask; it has been conjectured that the adhesive made the fabric preternaturally resilient, or that Zemo simply chose to not risk damaging his face further.) No longer confined to science only, Zemo started to lead combat and espionage missions and was rivaled in these only by the Red Skull; the two fast became rivals.

When it became apparent that the Nazis would lose the war, the Skull sent Zemo to London to steal an experimental airplane. At this point the plane would do them no good, but the Skull made sure this knowledge was leaked to Captain America and his young sidekick Bucky. The Skull knew that no matter who won, one of his enemies would be out of his way, possibly even killed. One of Zemo's androids knocked Bucky out, and Captain America was felled by Zemo's stun gun. They were tied to the plane, which was now booby-trapped to explode, and launched to their deaths. Captain America fell from the plan as it exploded, killing Bucky; he landed in the English Channel and was frozen in ice for decades until recovered by the recently-formed Avengers. Zemo, now living in South America, learned of his enemy's return and renewed the rivalry. He formed the Masters of Evil to serve as a villainous conterpart to the Avengers; the other founding members included the Black Knight, the Melter and the Radioactive Man, and they were later joined by the Enchantress and Wonder Man. In his final battle with Captain America, the captain's shield deflected a beam from Zemo's gun, which caused an avalanche that killed Zemo.

Baron Helmut Zemo

Zemo was survived by his son, Helmut Zemo, 13th Baron Zemo, who followed in his father's footsteps as a supervillain. He first surfaced under the codename of The Phoenix (not to be confused with any other characters who have used this codename), and was presumed deceased when he fell into a vat of specially-treated Adhesive X. As he had not been wearing his mask when he fell into the vat, his face was hideously scarred. (How an adhesive would leave acid-like burns is left unexplained, maybe those were the results of pulling off the dried glue.) He resurfaced years later, first allied with Arnim Zola's mutates and later with the Red Skull and his allies. Most notably, he formed a new incarnation of the Masters of Evil, one which invaded the Avengers' Mansion and crippled Hercules and the Avengers' butler Edwin Jarvis. Zemo was again believed dead, though he eventually returned, now married to a woman named Heike who had once called herself Baroness Zemo and had claimed to be the reincarnation of Heinrich Zemo.

Zemo, having abandoned Heike to prison, organized a new team of Masters of Evil when the Avengers and Fantastic Four disappeared and were presumed dead. These Masters of Evil took false identities and called themselves the Thunderbolts. Zemo led them under the alias of Citizen V until the missing heroes returned and the Thunderbolts' identities were revealed. Zemo left the team and was later killed by the new Scourge of the Underworld, though his mind was transferred, in electronic form, into his ally Fixer's mechanical "tech-pack". On the artificial world Counter-Earth - the same world to which the Avengers and Fantastic Four had vanished - the Thunderbolts encountered Zemo's counterpart in that world, Iron Cross. Fixer transferred Zemo's mind into his double's unmutilated body. Zemo then took up leadership of the Thunderbolts who were on Counter-Earth; when this group was reunited with their teammates who had remained on the normal Marvel Universe Earth, Hawkeye briefly resumed leadership but then left the team to return to the Avengers. Zemo is still currently the leader of the Thunderbolts, although as he is not the most loyal or trustworthy of characters, it is likely that he may turn on the team or be ejected.