William was the son of William and Ann Marsden (née Scott).
His father William was born in Market Rasen. Lincolnshire.
His mother Ann was born in Carlton in Lindrick, Nottinghamshire, in 1860, the daughter of Edward and Sarah Ann Scott (née Greatorex). In 1871 they were living at Marecroft, Worksop, with their three children, Henry, Ann and William. Ann had a daughter, Sarah Ann Scott (b. 1877, father's name not recorded), who in 1881 was living with her grandparents, Edward and Sarah at 51 Marecroft. Edward Scott died later that year and his wife Sarah probably in 1887. Their granddaughter Sarah Ann had a son, Frederick Scott, in 1894 (name of father not recorded).
William Marsden and Ann Scott were married at Worksop St Mary (Priory) in July 1879 and according to the 1911 Census completed by Ann she had had eight children, three of whom had died by 1911. Seven 'Marsden' children have been identified from census and birth registrations, one of whom is known to have died before 1911: George b. 1880, William b. 1882, Frances b. 1885 d. 1887, Annie b. 1890, Edwin b.1888, Arabella b. 1892 and Frances Gertrude b. 1898. It is possible that Ann had included her daughter, Sarah Ann Scott, who may have died by 1911, as one of her eight children.
In 1881 William a coal miner, and Ann, with their first child, George (under 1 year), were living at 63 Marecroft, Worksop.
In 1901, William senior, a coal miner hewer, Ann and five of their children, William, Edwin, Annie, Arabella and Frances Gertrude, were living on Pelham Street, Worksop, with their eldest son, George, a labourer, who was described as the head of household. Also in the home was Ann's grandson, Frederick Scott (7).
William jnr. married Isabella Bird at St Johns Church, Worksop, in 1908 and they had five children. two of whom died in infancy: William Cyril b. 1908 (J/A/S) d. 1908 (O/N/D), Queeny b. 1909 (O/N/D) d. 1911 (J/A/S), John William b. 1911, Lucy Lenorah b. 1913 and Gwendoline Victoria b. 1916.
By 1911 William senior, a labourer (quarry), was living at 15 Pelham Street, Worksop, in the home of his son Edwin, a coal miner hewer, his wife Lilian and their two children. Frederick Scott (17), an underground roadman in the mines, was also living with the family.
William senior's wife, Ann, was living at 4 Plants Yard, Bridge Street, Worksop, and described as married and head of household. In the home on the night of the census were her daughters, Arabella and Frances Gertrude, her son William, his wife Isabella and their daughter Queenie, together with another grandchild, George Marsden (9). George Marsden (George Robert b. 1902) may have been the son of Ann's eldest son George who had married Nellie Price in 1902 (J/F/M). Also in the household was a boarder, Walter Malkin, a general labourer.
William and Isabella later moved to 24 Trent Street, Worksop, and William's nephew, Frederick Scott, was living with them before he enlisted in 1914. Frederick served with the Sherwood Foresters and was killed in 1915. (See 'Extra information')
It is likely that William's widow Isabella remarried as there is a record of the marriage of an Isabel (sic) Marsden to George E Johnson in 1919 (reg. Worksop) and the record of the death of an Isabella Johnson in 1934 (reg. Doncaster). Her son, John William, was married in the Doncaster registration district in 1935 while both his sisters married in 1938, Lucy to Sidney Whitehurst and Gwendoline to Wm Snaith (both marriages registered Nottingham).