Sir Michael John Gambon is an acclaimed Irish-British actor who has worked in television, film and theatre.

Gambon was born in Dublin during World War II. His father, Edward Gambon, an engineer, decided to seek work in the rebuilding of London, and so Gambon and his seamstress mother, Mary (nee Hoare), moved to Mornington Crescent in north London, when he was five. Unbeknownst to Gambon, his father took out official papers for him, making him a British citizen--a decision that would later allow Michael to be awarded a substantive CBE and a knighthood.

Perhaps his most significant role in 2004, however, was Albus Dumbledore, Hogwart's headmaster in the third installment of JK Rowling's franchise, Harry Potter and the Prisoner of Azkaban, taking over from fellow Irish actor Richard Harris, who had died of Hodgkins disease. (Harris had also played Maigret on television four years before Gambon took that role.) Gambon reprised the role of Dumbledore in Harry Potter and the Goblet of Fire, which was released in November 2005 in the UK and U.S.. He returned to the role again in the fifth movie, Harry Potter and the Order of the Phoenix, which was released in 2007. Gambon admits to not having read the Harry Potter novels.

From Wikipedia