The red and white maple leaf ensign of Canada was a last-minute addition to the flag debate that had to be sneaked in to be considered at all.

In 1964, Prime Minister Lester Pearson decided he wanted the Canadian flag to be a three-maple leaf design on a white background, book-ended by two blue panels to convey the national motto "from sea to sea".

The design, known as Pearson's Pennant, had a mixed reaction, and after months of bitter debate he yielded to a cross-party committee to consider the issue.

The committee made little progress over six weeks. The Conservatives refused to budge on their demand that the flag have a Union Jack in a place of honour; the Liberals and others wanted a flag designed exclusively around the maple leaf.

One day historian George Stanley was walking with John Matheson, a Liberal MP on the committee, when he looked up and saw the Royal Military College flag and its vertical panels of red-white-red, with the college crest of a fist in the middle.

"There, John, is your flag," he said.

Mr Matheson recalls the moment: "I remarked that Canadians would not accept a mailed fist symbol. He said, 'No, I mean with a red maple leaf in the place of the college crest'."

Mr Matheson was immediately taken with it, but had to sneak it into the committee room to add it to the wall alongside the other proposals.

The committee firstly rejected the red ensign 10 votes to four.

They then had to vote on Pearson's Pennant, the red maple leaf ensign and the Union Jack or fleur-de-lis. When the latter was voted out, it was clear that the new flag would not have a Union Jack.

The Conservatives assumed the Liberals would vote for the Prime Minister's design, and they wanted the vote to be as inconclusive as possible, so they voted for the red maple leaf ensign which, to their horror, was the unanimous choice.

The flag still had to pass through Parliament, but not even senior members of the Conservative Party could stomach endless filibustering, and they invited the Government to end it.

The final vote took place in December 1964, approving the flag by 163 votes to 78, and on February 15 the following year, the maple leaf became the official flag of Canada.