John Bagot Cottam was born in Salford in 1836, the son of Richard Cottam and Margaret Bagot. He grew up in Manchester, where he was a warehouseman. Her married Adelaide Herbert, daughter of Reuben and Ellen Herbert, in 1858, and their first three children, Margaret, Ada and Jessie were born in Manchester.
He came to Natal in 1863 as accountant to the Natal Cotton Plantation Company. The American Civil War had disrupted the supply of cotton to the Manchester cotton mills, and it was thought that Natal might be an alternative source of supply. That soon fell through, however, and in 1867 J.B. Cottam set up business on his own account as a wool presser and fresh produce dealer. When the Durban fresh produce market was opened in 1876, he became the first market master. In 1891 he became a city councillor. For two terms he served as a town councillor of Durban until he retired in 1894. He then started his own business as accountant and auditor at 61 Esplanade Buildings.
Like many people of his time, he was a member of the Freemasons and other social and charitable organisations. He was district Grand Warden EC since 1887. He was district grand secretary for 12 years and held other offices in the Craft as well as being a prominent member of the Durban Town Guard formed during the Zulu War. He was also treasurer of the Durban
Benevolent Society for several years and occupied the position of secretary to the Seamens Institute.
He took an active interest in church affairs, and was one of those who supported the Colenso schism from the Anglican Church in Natal, and was at one time publicly rebuked to be Bishop of Natal for preaching without a licence from the bishop.
They had five more children in Natal: Richard Herbert, Lucy, Bessie, Lily and Kate.
John Bagot Cottam’s younger brother, William Henry Cottam, also came to Natal, and farmed near Verulam.