Montague Ely Sainsbury (1905-1998) began trading as an antique dealer in 1933 in London Road, Southampton, where his father Daniel T. Sainsbury ran an antiques business, his father having first begun in business as a builder. His brother, Clarence Ferris Sainsbury (1910-1975) was also a dealer in fine art and antiques. Montague closed the Southampton business at the start of the Second World War, and worked as a lathe operator for Folland Aircraft Co. in Southampton. He started dealing in antiques again from his home in Southampton after the end of the war, before moving the business to 35 Gay Street, Bath, taking over the shop of the dealer Reginald Way in 1951. He remained at Gay Street until his death in December 1998.
Christie's South Kensington held an auction sale, 'The Montague Sainsbury Collection' on 6th & 7th July 1999, following the death of Montague Sainsbury.