Sackville was born in or before 1501. His family had lands in Essex. By 1529 he was a lawyer, qualifying through
Gray's Inn. Among his posts were estate management, the stewardship of lands and estates connected with Arundel Castle though his association with the Earls of Arundel, and the Sussex bench. He was a
Member of Parliament (MP) for
Arundel in 1529, which may not have been his first or last such election. ==Personal life==