Jennings River adopted in the 1st Report of the Geographic Board of Canada, 1898, as labelled on Geological Survey sheet 256, Yukon and Part of Northern British Columbia, published in 1898 to accompany report of George Dawson; not "Fifteen Mile River" as identified in other early maps.

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

Named after W.T. Jennings, CE, of Toronto, who conducted surveys in the region c1897, probably in association with the proposed Stikine-Teslin railway. This feature is not compiled on BC Lands Dept. 1895 map of British Columbia. No further information about Jennings' work in the north; he is known to have conducted surveys in the Chilcotin, 1875-76.

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

The Tlingit name for Jennings River is Six' aati Heen, meaning "abundant river" - this area is close to Johnston Town, just past there. There is a lot of game in that area; X'aati means "placenta of game animal" (such as moose). (Information provided August 2012 by Teslin Tlingit Council, in turn confirmed in summer 1999 by Jimmy Johnston and Frank Jackson.)

Source: included with note