"Cowichan Bay (steamer landing, settlement)" identified in the 1930 BC Gazetteer. Form of name changed to Cowichan Bay (post office & steamer landing) 8 July 1948. Form of name changed to Cowichan Bay (community) 15 December 1982 on 92 B/12.

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

Cowichan Bay Post Office was opened 1 November 1907; closed 30 June 1921; re-opened 1 January 1941.

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

The bay was named about 1850 by officers of the Hudson's Bay Company for the powerful Coast Salish First Nation - the most populous in BC - that occupies this territory (and now spells its name Quw'utsun'). Cowichan Lake, Cowichan Station, the Cowichan Valley Regional District, etc, all derive their names from the same name source. Cowichan is an adaptation of an Island Halkomelem term for "warming the back," which, in turn, refers to a bare, rocky formation on the side of Mount Tzouhalem, said to look like a frog sunning itself. There were many variants of this name in the old days, includeing Cowichin, Cowitchin, Cowitchan, K'au'itchin and Ka-way-chin. The earliest version recorded probably that of the Hudson's Bay Company trader John Work, who mentioned the Coweechin in 1824. In fact, so many Quw'utsun' people migrated across the Straights of Georgia each year to occupy summer village sites on the Fraser and harvest its great salmon runs that Work identified that river as the Coweechin. The Songhees First Nation name for Cowichan Head, the northern boundary of their territory, was Tiumalatchung.

Source: Scott, Andrew; "The Encyclopedia of Raincoast Place Names"; Harbour Publishing, Madeira Park, 2009, pp. 137-138.

"Harrisville" identified on BC name card as old name for Cowichan Bay (map/document title or date not cited)

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