Record 001 · Sovereignty
Known by this name since at least 1641.
“We're going to be changing the name of Lake Ontario to Lake America.”
Donald Trump · Public remarks · August 26, 2026
The name Ontario appears in the written record by at least 1641, and it is of Indigenous origin.
Historical sources differ on the precise source word and its translation — "sparkling water" or "beautiful lake" — but not on where the name comes from.
Each block answers one question: what does this source establish?
Evidence 01
Natural Resources Canada's Geographical Names Board states the earliest recording of the name was in 1641. The Canadian Encyclopedia records that the name was first applied to the lake by Europeans in that year.
Evidence 02
Natural Resources Canada and the Government of Ontario both give the Iroquois word "kanadario", "sparkling water". The Canadian Encyclopedia describes the name as Iroquoian, meaning "beautiful lake" or "sparkling water". The sources differ on the precise word and translation, not on the origin.
Natural Resources Canada
Origin of the names of Canada and its provinces and territories — Geographical Names Board of Canada
States the earliest recording of the name was in 1641 and gives the Iroquois word "kanadario", "sparkling water". Page modified 2025.
View original →Government of Ontario
About Ontario — origin of the word "Ontario"
Gives the Iroquois word "kanadario", meaning "sparkling" water.
View original →The Canadian Encyclopedia
Lake Ontario — naming of the lake
States the name was first applied to the lake by Europeans in 1641, and is thought to be Iroquoian, meaning "beautiful lake" or "sparkling water".
View original →Last checked:
Film credits
Music from #Uppbeat — Simon Folwar, "Enemy at the Gates" · License code: LFL85D3OMIBAVV7S
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