Roche Déboulé Mountains adopted 7 January 1913 on Ottawa file OBF 0024. Form of name changed to Rocher Déboulé Range 14 February 1918, and so-identified in "Mountains of Western Canada" published by the Geographic Board of Canada, 2 April 1918.

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

Charles Horetzky in his 1874 report to CPR (p.102) noted the name Rocher Déboulé, south of Hazelton. George Dawson's map "British Columbia & North West Territory from the Pacific Ocean to Fort Edmonton" to illustrate Geological Survey of Canada report 1879-80, labels Rochers Deboules [sic]. The village of Ackwilgate [sic] and Mt. Rocher Deboule [sic] just to the south, are labelled on "Map of the Northern Interior of British Columbia" by A.G. Morice, OMI, 1907.

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

"Five miles from Hazelton, which stands at the junction of the Bulkley River with the Skeena... is the Babine village of Rocher Déboulé, or Ackwilgate, as the Tsimsians have it. Rocher Déboulé means Fallen Rock, from part of the mountain just back of it which formerly fell off into the river." (Fifty Years in Western Canada, by Rev. A.G. Morice, OMI; Ryerson Press, Toronto, 1930, p.111, extracted from Morice's 1900-1904 memoirs.)

Source: included with note

Mis-spelled "Rocher Débroulé Range" on federal 1:50 000 map 93M/4, ed 3.

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