Thunderbird (John Proudstar) is a comic book superhero in the Marvel Comics universe, and a member of the X-Men. He first appeared in Giant-Size X-Men #1 (May 1975).
Proudstar is an Apache Native American who had once been a corporal in the United States Marine Corps. He was recruited by Professor Charles Xavier to join his second group of X-Men. Although Proudstar had a big chip on his shoulder towards white men, he agreed. His tenure with the team was short, however, as he was killed trying to stop a ploy by Count Nefaria (in X-Men #95).
Proudstar possessed great strength, agility and damage resistance.
He is survived by a younger brother, James, who also adopted the name Thunderbird. James has similar abilities yet much greater physical strength.
An alternate world version of John Proudstar is a member of the dimension-hopping team The Exiles. This Thunderbird was captured and modified by Apocalypse before escaping and turning on his captor. As a result he is a half-machine creature with immense strength and damage resistance, capable of taking on The Incredible Hulk. However, he was injured in a battle with Galactus and was left in a coma in that dimension. His ultimate fate is unknown.