Peter was born to Jesse Mangnall (GM107) and Alice in about 1873 in Westhoughton. At the time of the 1881 census he is describes as a scholar living with his parents at Warrington Road Kingsdown Terrace in Abram.
By the time of the 1891 Census the family had moved to 8 Wright Street in Abram and Peter was now working as a coal miner like his older brother.
Peter had married Jane by the time of the 1901 Census and they had moved next door to 10 Wright Street. Peter and Jane had the following children:-
- Jane, born c.1897;
- Alfred, born 1898.