Born at Kingston, Upper Canada, he was the second son of Joseph Forsyth (1764–1813) and his wife Alicia, daughter of Major James Robbins of the Royal Artillery.
Through his grandparents he was connected to the important London trading house of Phyn, Ellice & Co., a subsidiary of which was Forsyth, Richardson & Co., of Montreal, where two of his uncles, Thomas and John Forsyth, were partners; this firm prospered in the fur trade and expanded into other activities such as the agent and forwarding business.
James and Frances Forsyth were the grandparents of General Sir Henry Edward Burstall and The Hon.
[1][2] He was buried on 5 April 1869, at Mount Hermon Cemetery, located at a short distance down Saint-Louis Road from his estate of Cataraqui.
[1][2] His son Joseph Bell Forsyth and son-in-law John Burstall were recorded in the parish register as having been present.