It took almost a century of efforts and bitter debates before the Canadian flag finally changed - becoming a symbol that now resonates as one of national pride.

From 1867 until 1965, Canada had regularly used both the Union Jack and the Canadian Red Ensign - which had a Union Flag in the corner and a shield with the coat of arms - as a national flag. But officially there was none.

Several nationalist movements had tried to adopt an official national flag without success. The early movements focused on what the national symbol should be - A maple leaf? A beaver? The fleur-de-lis lily flower? - while the later ones debated whether the Union Jack had a place.

In 1946, Prime Minister Mackenzie King turned down a committee recommendation for a national flag of the red ensign with a gold maple leaf. His criticism? That the committee's support was not unanimous; the vote was 23 to one in favour, with 11 abstentions.

Part of the problem was that the committee's choice had a Union Jack on it, while only 14 per cent of 2700 submitted designs retained the British link.

The issue had been temporarily sunk but the debates in Parliament continued, even as power shifted from Liberal to Conservative hands in 1957.

The following year, a poll showed that 80 per cent of the public wanted a national flag entirely different from that of any other nation, and three-fifths wanted it to bear the maple leaf.

But when asked to solve the problem of the flag in 1960, Prime Minister John Diefenbaker, an imperialist and stalwart of the Union Jack, refused.

In response, Liberal leader Lester Pearson made adopting a national flag an election promise and, when elected in 1963, set a two-year timeframe.

Of many designs floated, he preferred a three-maple-leaf design on a white background, book-ended by two blue panels to convey the Canadian motto "from sea to sea".

Despite criticism, the flag's supporters ranged from nationalists to "Toronto nightclub strippers who climaxed their acts by jiggling on stage with three strategically placed red maple leaves", wrote Alistair B. Fraser in The Flags of Canada.

A year later, the Prime Minister opened parliamentary debate by resolving to establish his favoured design as the national flag.

Mr Diefenbaker, by then in opposition, said: "Surely Canada deserves something better than ... the symbol of three maple leaves."

After much acrimonious debate, the Prime Minister agreed to send the matter to a cross-party committee. It had six weeks to report back and received 3541 entries; 2136 had maple leaves, 408 had Union Jacks.

Committee meetings descended into shouting matches as the deadline loomed.

When they decided to unanimously back one design, the Opposition continued to filibuster in Parliament until, after another weary six weeks, two frustrated Conservatives invited the Government to cut off the debate by applying closure.

The final vote in December 1964 passed by 163 to 78.

The flag became the official banner of Canada on February 15, 1965.

"The national flag has now became fused with the Canadian identity so comfortably that it is now hard to imagine the nation without it," wrote Fraser.

A difficult birth:

1867 - The Canadian Confederation uses different flags as a national flag, including the Union Jack and the Red Ensign, which has a Union Jack in the upper left corner. But there is no official national flag.

1946 - Prime Minister Mackenzie King turns down a committee recommendation to adopt a national flag of the red ensign with a gold maple leaf. The committee voted 23 to 1 in favour, with 11 absentees.

1958 - A poll shows that 80 per cent of the public want a national flag entirely different from that of any other nation, and three-fifths want it to bear the maple leaf.

1960 - Opposition leader Lester Pearson demands that Prime Minister John Diefenbaker solve the problem of the flag, but is refused. Pearson promises in the lead-up to the 1963 elections to adopt a national flag.

1964 - Pearson, now Prime Minister, resolves in Parliament to establish a maple leaf ensign as the national flag. Bitter debate forces him to hand the matter to a cross-party committee.

Dec 1964 - Final vote on the flag. New ensign wins by 163 votes to 78.

Feb 15, 1965 - The maple leaf ensign becomes the new official flag of Canada.