Captain Britain
Captain Britain (Brian Braddock), also briefly known as Britanic, is a comic book superhero in Marvel Comics' Marvel Universe.
History
The Braddock family has supplied Captain Britains to guard the British Isles for centuries. Following a motorcycle accident, physics student Brian Braddock was recruited by Merlin to be the latest incarnation of Captain Britain, a role he felt himself unsuited for. He joined forces with Spider-Man and the Black Knight early in his career, then returned to Britain first as a lone hero and then as part of Excalibur.
Every Earth in the Marvel Multiverse has its own Captain Britain who is expected to defend that version of the British Isles and uphold its local laws. For example, on one Earth the Nazis won World War II, so its Captain Britain ("Hauptmann Englande") upholds the Nazi regime. On another Earth, mutants have been eradicated and Captain Britain runs a league of enforcers who hunt down any remaining mutants. In some of these alternate universes Captain Britain is the alternate version of Brian Braddock, in others it is someone completely different. The Earth of the "normal" Marvel Universe is Earth-616.
Brian has two super-powered siblings: his twin sister Psylocke of the X-Men and his older brother Jamie, once a playboy, now a madman with the ability to bend reality to his will. He is married to Meggan, an empathic metamorph.
Some sources suggest that he may be a recovering alcoholic, but this is unconfirmed - that opinion seems to come almost exclusively from his behavior at a time when he believed his sister dead.
Powers and skills
Captain Britain has superhuman strength, the ability to fly, and near-invulnerability. However, all of his abilities are localized to Britain; if he goes abroad for too long a time, he grows sick and weak. His costume acts as an antenna, allowing him to retain his powers no matter how far he goes from Britain. He is also a scientist, though he rarely has the opportunity to exercise his training as a physicist.