Adopted 7 June 1927 on BC map 4M, as labelled on Trutch's 1871 map of British Columbia, and on Dawson's 1895 map for Geological Survey of Canada, 556 & 557, Kamloops. (Ottawa file OBF 1140).

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

"The name of the Chief of the Indians who lived in this place in the 1830's. Early records spell his name Sanquil. The name applied to the man, not the place. Usually the name is spelled Tranquil. The spelling Tranquille seems to have been introduced after 1870."

Source: Provincial Archives of BC "Place Names File" compiled 1945-1950 by A.G. Harvey from various sources, with subsequent additions

"Bancroft says the river was named after a Shuswap chief whose sauvity led French Canadians in the fur trade to call him Tranquille. However the name is shown on Archibald McDonald's sketch of Thompson's River District, 1827, and it seems possible that it was given to describe the quiet flow of the river, and that the chief took his name from the river. The chief died in 1841 and got notoriety in a peculiar way: his widow persuaded a young nephew to murder Samuel Black, HBC chief trader at Fort Kamloops, because he had scolded the chief shortly before his death and was suspected of having charmed his life away."

Source: Provincial Archives of BC "Place Names File" compiled 1945-1950 by A.G. Harvey from various sources, with subsequent additions

"Chief Pacamoos, nicknamed Tranquil by the fur traders, was noted by Archibald McDonald in 1827 as head of the lower Shuswap tribe, and seems to have been on very friendly terms with the white men. But when he died in camp at Pavilion in 1841 his nephew Kiskowskin was for some reason induced to kill Chief Factor [trader] Samuel Black - the saddest event in the generally happy Indian anbd HBC history here."

Source: Place Names of the Kamloops District; Kamloops Museum, 1978

"Named after a local Indian chief whose quiet easy manner led the whites to refer to him as Tranquille. His death in 1841 led to the murder at the HBC post at Kamloops of Chief Factor Samuel Black. For the story see Akrigg, British Columbia Chronicle, 1778-1846, pp.325-27)"

Source: Akrigg, Helen B. and Akrigg, G.P.V; British Columbia Place Names; Sono Nis Press, Victoria 1986 /or University of British Columbia Press 1997

Headwaters at 50 57 - 120 43 on 92I/15.

Source: Canadian Geographical Names Database, Ottawa