Frederick Duleep Singh was the son of the deposed and exiled Maharaja Duleep Singh of the Punjab. Born in Kensington and bought up at the family home in Elveden, Suffolk, Frederick (or Freddy) was educated at Eton School and then studied history at Magdalene College, Cambridge. Like his father, he enjoyed shooting and country estates. In 1906, he rented Blo Norton Hall in Norfolk, and lived there for the rest of his life (twenty years). In the summer of 1906, Virginia Woolf had stayed at Blo Norton Hall and it provided the setting for her short story, 'The Journal of Miss Joan Martyn'. Frederick Duleep Singh became an amateur archaeologist and historian, specializing in East Anglia and its gentry. He contributed to a number of local periodicals and built up a collection of English artefacts in his home. In 1921, he bought Ancient House in Thetford and gave it to the town as a museum. His collections were donated to Thetford Museum, the Museum of Inverness and Norfolk Record Office.

Frederick joined the Suffolk yeomanry as Second Leutenant in 1893 and was promoted through the ranks. In 1901, he was transferred to the Norfolk yeomanry as Major. In 1909, he resigned from the yeomanry, but at the outbreak of war in 1914 he rejoined. He served in France with training units from 1917 to 1919, but saw no action.

Frederick Duleep Singh did not visit India and was a conservative, Christian loyalist. He was a member of a number of societies, including the Society for the Protection of Ancient Buildings, the Norfolk and Norwich Archaeological Society (President in 1925–6), the Norfolk Archaeological Trust, the London Society of East Anglians (President), the Royal Norfolk Agricultural Association,  and the Diss Choral Society, and belonged to White's and the Carlton Club in London.