OTTAWA -- When he jumped out of his landing craft into knee-deep water off the coast of Normandy on June 6, 1944, Jack Commerford wasn't contemplating the role he was about to play in what would become one of the most pivotal events in history.

The 20-year-old from Newfoundland and Labrador, who had joined the army three years earlier to shoot down German bombers, was too busy doing his job -- and trying to stay alive -- during the long-awaited Allied assault to free Europe from the Nazis.

"I was just thinking of my duties at the moment," recalls Commerford, now 95. "Go where I was sent and do what I was told, that was primarily what I was interested in. I'm not sure how much I thought of the overall war."

The invasion of Normandy is widely considered one of the turning points in the Second World War, as the allies smashed through Hitler's supposedly impregnable Atlantic Wall and began the westward march to Berlin to meet the Soviets coming from the east.

But in Canada, which had come into its own in the wake of Vimy Ridge and the First World War, D-Day and the conflagration that spawned it gave the country the chance to find its feet and establish its standing in the world.

"D-Day makes us winners," says retired major Michael Boire, an expert on Canadian military history at the Royal Military College of Canada. "It makes us winners in our own eyes. And that's tremendously important."

That wasn't always the plan.

At the start of the war in 1939, then-prime minister William Lyon Mackenzie King, fearing another conscription crisis, wanted to keep his country from becoming too deeply involved. Conscription, introduced in 1917, nearly tore Canada apart during the First World War as many Canadians, particularly in Quebec, railed against being forced to fight in Europe.

Mackenzie King adopted a policy of "limited liability," in which Canada's main contributions were small contingents of troops to help defend England and the provision of food, equipment and training to assist the allies.

"But the war doesn't go the way anybody expects," says author and historian Jack Granatstein, former head of the Canadian War Museum.

"The Germans in 1940 sweep everything away and all of a sudden Canada is Britain's major ally. From being a limited liability participant, suddenly we are the major ally of Great Britain. And so all the stops are pulled on the war effort in Canada."

That included retooling Canada's fledgling industrial base to start mass producing weapons, aircraft, warships and tanks, which in turn laid the groundwork for the future innovation and economic prosperity that Canadians know today.

"We go from being a poor country in a very real sense to being a rich country at the same time as we're fighting the war," says Granatstein, who notes Canada's gross domestic product doubled between 1939 and 1945.

In 1931, Canadians became masters of their own affairs with the Statute of Westminster, a British law that effectively made Canada a sovereign nation. With D-Day and the war, the country was soon basking in a newfound self-confidence matched only by its desire for peace.

That manifested itself in Canada's role as a founder of the North Atlantic Treaty Organization, established primarily to check Soviet aggression in Russia, and its strong support for international institutions such as the United Nations to push for a rules-based international order.

"It was clear Canada had entered the international scene, it was a player at the table," said Boire. "And Canadian public opinion is all about getting involved in every single international organization that's around and ... participating in the avoidance of war."

Sitting at the Perley and Rideau Veterans' Health Centre in Ottawa, with his military medals pinned proudly to his chest, Commerford echoes that assessment.

"It shaped Canada into being a wonderful, peace-loving country," he says.

"I see Canada and its leaders as continually doing things that will encourage or help maintain peace, not only in Canada but also elsewhere. And I think D-Day and the Second World War contributed to that strong desire for peace."

Canada started the war with a regular army of 4,200. Eventually, around 1.1 million Canadians would serve in uniform. They were everywhere, be it bombing German cities, escorting naval convoys across the Atlantic or fighting house to house in Italy.

But D-Day was the big one, the attack everyone had been waiting for. And while two of the Normandy landing beaches were assigned to the Americans and two to the British, the fifth -- an eight-kilometre stretch code-named Juno -- was all Canadian.

"One of the five beaches is ours," says Canadian War Museum historian Tim Cook. "We must take it. And one of the challenges for D-Day is if one beach fails, they're likely all to fail."

Years of preparation and training following the hard lessons of Dieppe -- the disastrous raid two years earlier in which 900 Canadians were killed and nearly 2,000 captured -- were put to the test when the first landing craft hit the beach at 7:45 a.m.

The casualties in that initial wave were heavy as the Canadians advanced into a maelstrom of German fire; by the end of the day, 340 would be killed -- more than twice the number who died during Canada's entire 13-year war in Afghanistan. Another 574 were wounded.

Yet the assault was a success. The Canadians advanced farther than anyone else on that first day while Canadian pilots guarded the skies and more than 100 Royal Canadian Navy ships manned by 10,000 Canadian sailors guarded the English Channel or ferried troops and equipment to shore.

One of those was Alex Polowin, who served aboard HMCS Huron and compares the feeling of battle to how a boxer feels as he prepares to fight an opponent.

"Most of our battles were at night and we'd come out there and all of a sudden starshells fly over your ship. Starshells light up the sky to bring out your silhouette," says Polowin, now 94.

"You've got fear in you, you've got to hate that person. You get that adrenaline rush forced on you in boxing. But this was natural."

The war would grind on for nearly another year. Some of the hardest fighting would happen after D-Day, as the allies pushed out of the beaches and into the rest of western Europe. By the end, 45,000 Canadians in uniform had lost their lives in the war.

But D-Day has tended to overshadow those Canadian efforts, which includes the Battle of the Scheldt, the Battle of the Atlantic and the liberation of Italy. In 1999, D-Day was selected the Canadian news event of the century in a survey by The Canadian Press.

"Canada is fundamentally changed by the Second World War," says Cook. "To pick an isolated event is too simplistic, but D-Day becomes a symbol."