Seymour Creek adopted in the 15th Report of the Geographic Board of Canada, 31 March 1917, as labelled on BC Lands' 1905 map of New Westminster District, and on BC map 2B, 1914. Form of name changed to Seymour River 6 May 1947 on 92G/6.

Source: BC place name cards, or correspondence to/from BC's Chief Geographer or BC Geographical Names Office

Main channel of Seymour River identified as "East Branch of North Fork of Seymour River" in the 1930 BC Gazetteer.

Source: BC place name cards, or correspondence to/from BC's Chief Geographer or BC Geographical Names Office

Named after Frederick Seymour (1820-1869), who had succeeded James Douglas as Governor of the Colony of British Columbia (ie. mainland portion only), 1864-69. Also Mount Seymour. Note that the exact date these features were named is not known. British Admiralty Charts 922 and 1922, published through 1886, locate but do not label these features.

Source: BC place name cards, or correspondence to/from BC's Chief Geographer or BC Geographical Names Office

Governor Frederick Seymour arrived 20 April 1864. On landing from HMS Forward, Governor Seymour was presented with addresses of welcome from City Council and people of the Colony. Died 10 June 1869.

Source: Nelson, Denys; Place Names of the Delta of the Fraser River; 1927, unpublished manuscript held in the Provincial Archives

Headwaters at 49 35 -123 02 on 92G/11.

Source: Canadian Geographical Names Database, Ottawa