Theo James was born in Oxford, Oxfordshire, the son of Jane and Philip Taptiklis. His paternal grandfather was Greek (he moved from the Peloponnese to New Zealand). Theo James other ancestry is English and Scottish. The youngest of five children, Theo has two brothers and two sisters. Theo James attended Aylesbury Grammar School and went on to earn his undergraduate degree in philosophy from the University of Nottingham. He trained at the Bristol Old Vic Theatre School.