Martineau was born to the pianist Hester Dickson Martineau and Canon George Martineau in 1960. He was an only child but he had several step siblings from his parents' previous marriages. He was born in Edinburgh, and educated at George Watson's College. He studied at St Catharine's College, Cambridge between 1978 and 1981 and went on to study at the Royal College of Music between 1981 and 1984.
