Kenneth Robertson was born in Kirkintilloch, Dunbartonshire, Scotland. After leaving school he moved to London to join a touring theatre company that performed throughout Britain. He later trained as a teacher of Art and Drama but continued being an actor and did an MA in Theatre Performance at Goldsmith's College, London.

As an actor he has worked in Children's theatre, The Young Vic. Community Theatre, Fringe Theatre, London's West End, The Royal Shakespeare Company, Cheek By Jowl as well as many TV series/plays and film.