It was 85 years ago this Tuesday that many historians say Canada took its place as a nation on the world stage.

On April 9, 1917, Canadian soldiers, fighting under their own commander for the first time, launched an assault on Vimy Ridge that would be a turning point in the First World War.

Hundreds gathered Tuesday morning at the War Memorial in Ottawa to pay tribute to the thousands of Canadians wounded or killed in the battle. It was one of the toughest battles ever fought by Canadians, say soldiers who made it out alive.

"It took a few hours to get them sorted out, and get them cleaned out of there, and take the prisoners back," Phillip Downey, age 107, of Point de Chene, New Brunswick said in a 1998 interview, before his death.

The 1936 documentary Lest We Forget recalled the historic day: "Zero hour, 5 a.m., April 9th. Then, in one great, great chorus of deafening explosions, the greatest mass of guns so far concentrated on the western front belched their shrieking missiles onto Vimy Ridge."

"There had been attempts by allied armies to seize this ridge, for a number of years, repeated attempts, and they had failed," University of P.E.I. history professor Ed Macdonald said.

"The Canadians, through careful planning, leadership and bravery, and a little bit of luck perhaps, were able to take the ridge, and that sent shock waves through the allied armies. The Canadians had done it."

More than 130,000 French forces were killed trying to take the fortified area two years earlier.

"We took it and held it, and they never tried to come back," Wilfred Chapman of Peterborough, Ontario said in 1997, at age 99, just before his death. "Through a snowstorm, the Canadians plowed across no-man's land, into the enemy trenches. Enemy machine guns tore through them, but with little heed to conditions or casualties, the Canadians pressed on."

During the assault, 3,598 Canadian soldiers were killed and more than 7,000 more were wounded. But military experts say the morale boost the victory provided was the turning point in the war.

The Vimy Ridge attack, say historians, proved to the British that Canadians were "shock" troops, the vanguard of the British army.

Defence Minister Art Eggleton agreed the battle "helped define Canada as a nation."

"The Canadians were known, you know...If there was a tough place to take, they'd use the Canadians," Vimy Ridge veteran Wilfred Chapman said. "We took Vimy Ridge, even when others said they couldn't."