Brand was the eldest son of soldier and courtier Thomas Brand, 3rd Viscount Hampden, and of his wife Lady Katharine Mary Montagu-Douglas-Scott, a daughter of the 6th Duke of Buccleuch, and was born 30 March 1900 at the home of his maternal grandfather, Montagu House in London.
After Eton, he joined the British Army and was commissioned as a Lieutenant into the Rifle Brigade.
They had four daughters, Sarah Elizma (1924–1937), Gian Katherine (1927–1929), Rachel Leila (1929–2012), and Tessa Mary (1934-2020).
In 1931 he became Managing Director of Lazard Brothers & Co. During the Second World War he served as Chief Executive Officer on the British side of the Combined Production and Resources Board, from 1942 to 1944, then from 1944 to 1945 was Chairman of Supplies for Liberated Areas Official Committee.
However, the abeyance was terminated in 1970 in favour of his elder surviving daughter Rachel Douglas-Home, 27th Baroness Dacre.