C.F.G. Castleman was the son of of a gentleman landowner, who took up photography for a short time in the mid 1860s. Castleman was born in Shirley, Southampton and his family moved to a villa in Woolston soon after his birth. The 1871 census recorded Castleman as a retired photographer living with his wife and young son in the Woolston villa.
By 1881 C.F.G was the owner of a substantial farm in Bursledon. In 1891 he was 'living off his own means' while his eldest son, Frederick was running the farm. C.F.G died in Bursledon in 1919.