William was the second son of Samuel Henry Comor (previously Samuel Hirsch Komorower) and his wife Annie. The first in the family to be born in Britain, his father was still Austrian according to the 1911 census. His father was an agent in Cotton but soon took over the Boarding House at 1 Warley Road Blackpool and advertised the place as 'The only Jewish Boarding House on the Promenade'. The family became stalwarts of Blackpool Jewry with Samuel being on several committees.
His elder brother Maurice was sadly killed during the war. By the time of the 1939 household survey, William was living with the family in the Boarding house in Blackpool, alhough he gave his occupation as Manufacturing chemist. By the time of his father's death in 1927 he describes himself as a costumier.