Slesse Mountain adopted 6 October 1936 on Geological Survey sheet 422A, Hope, as labelled on Geology of the 49th Parallel, sheet 16, to accompany GSC Memoir 38, 1912, and on BC Lands' map 2B, 1914, and on BC map #18, Okanagan, 1923, and as identified in the 1930 BC Gazetteer. Name changed to Silesia Mountain 5 April 1951 on 92H/4, to conform to spelling used in Washington State. Name changed back to "Slesse Mountain (not Silesia Mountain nor Mount Slesse)" 5 July 1951 on 92 H/4, as advocated by BC Geographic Division (file C.1.50 pt.1)

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

"This name, pronounced suh-LEE-see, comes from the original language of the Chilliwack Indigenous people and means 'fang.' It is very descriptive of the mountain's appearance."

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

"The name Slesse is 'fang' in the Salish tongue; some Boundary Survey sketches labelled the peak "Turret" although another early name was "Tomahi" (meaning 'high places')....." (from: Cascade Alpine Guide by Fred Beckey, ed.1, 1981, p.129-136, with photographs)

Source: included with note

The name was borrowed and applied to the adjacent creek: spelled "Selacee Creek" on International Boundary Survey Reports, 1860. Spelled "Slesse Creek" on Royal Engineer's map of British Columbia, 1862, and on Trutch's 1871 map of BC, and on G.M. Dawson's 1877 map of the Southern Interior of British Columbia. The first appearance of the name applied to the feature to which it correctly refers (ie. the mountain) seems to be Geology of the 49th Parallel, sheet 16, to accompany GSC Memoir 38, 1912.

Source: BC place name cards, files, correspondence and/or research by BC Chief Geographer/Geographical Names Office.

The location of the worst aviation disaster in BC history: on 9 December 1956 a Trans Canada Airlines plane heading east out of Vancouver with 62 passengers and crew, crashed into the mountain in bad weather. The site of the crash was so isolated that it was not discovered by mountaineers until 11 May 1957. The coroner was landed by helicopter, and mountaintop funeral and burial ceremonies were held for the victims later in the summer. A cairn was erected on the site 11 September 1957.

Source: BC place name cards & correspondence, and/or research by BC Chief Geographer & Geographical Names Office.