Challenger was the world's first superhero. Stephen Kennedy (no relation to the political Kennedys) was a millionaire industrialist and owner of Kennedy Industries and leading Defense contractor, who first discovered he had enhanced abilities in late 1959. Stephen's abilities came to the attention of the US government in late 1960. With the reappearance and resurgence in popularity of superheroes in comic books and the new Kennedy administration's forward-looking approach, the idea of a real-life costumed superhero seemed like a good idea. On July 15, 1961, President John F. Kennedy introduced Challenger to the people of the United States as a "hero to face the challenge of the New Frontier".
Always a patriot, Stephen happily put his enhanced strength and dexterity along with his fighting and tactical skills to work as the nation's premier superhero. Some future historians would refer to Challenger as the Lancelot of the Kennedy Camelot.
Over the next several years, other superheroes began to appear and in 1966, SuperSquad America was formed with Challenger as its leader. He led the team from its inception until he disbanded it following the tragic events of the Bicentennial Incident. The government honored Stephen by naming a space shuttle after him.
In the 1990s, Stephen's son David continued the Challenger legacy as leader of a new SuperSquad America.