 Lawrence was born on 9 February 1913, the son of Aubrey Trevor Lawrence KC, MBE and his wife Constance Emily Fanning.He was the grandson of Sir Trevor Lawrence, 2nd Baronet and was, until his death, heir to that title.He was educated at Eton, where his godfather, Cyril Alington, had recently been appointed head master, and at Christ Church, Oxford, his father's college, where he read science and mathematics.