Philéas Côté introduced a 1946 private member’s bill to rename Dominion Day as Canada Day.
Côté was a Quebec Liberal and Independent Liberal member of Parliament for Matapédia—Matane. He entered the House of Commons after the 1945 federal election and soon pursued changes intended to strengthen Canadian national identity, including official recognition for “O Canada.”
His bill passed quickly in the House of Commons, but the Senate proposed replacing “Canada Day” with “The National Holiday of Canada.” That amendment stalled the proposal, so Dominion Day kept its name for decades. The holiday was not officially renamed until 1982, when Parliament passed a new private member’s bill.
A common mix-up is to credit the 1982 change to the same person who proposed the 1946 bill. Côté made the early attempt; the successful renaming occurred 36 years later and took effect after royal assent in October 1982.