Percy was born in 1895 in March, Cambridgeshire. In 1911 at the age of 16 he was living in Stamford at 28 Wharf Road with his parents Arthur John and Ellen (nee Harley) Large and his sister, Lily (9). His father was born in Clenchwarton, Norfolk and his sister was also born in March. His mother was born in Chesterfield, Essex. Father was an electrician and gas fitter in an ironmongers. His mother worked at home as a costumier. Percy was employed as a grocer’s apprentice. They had moved to Stamford from March where they were living in 1901.

At the time of the1901 Census three year old Percy was visiting his paternal grandparents, John and Harriet Large in St John’s Terrace, Kings Lynn. His grandfather was a mail contractor. His parents were at 36 High Street, March. After the 1911 Census no records of the family have been found.