He did his national service as a second lieutenant in the 11th Hussars,[1] receiving his commission on 3 November 1951,[2][3] and was educated at Magdalen College, Oxford.
[1] On 30 September 1952, he was transferred from the national service list to the Queen's Own Yorkshire Dragoons, with seniority from his original date of commission.
[13] After leaving the Army, Lumley took part in horseracing as a member of the Jockey Club and a steward at Doncaster and York.
In 1970 he married Lady Elizabeth Anne Ramsay, oldest child and daughter of Simon Ramsay, 16th Earl of Dalhousie,[1] and had four children and one granddaughter: Widely respected by the inhabitants around Sandbeck, he joined the miners in protesting a proposed closure of Maltby pit.
[1] He was forced to sell furniture to meet his father's death duties, and thereafter he and his wife worked to restore and preserve the family estates at Sandbeck Park and Lumley Castle.