The Battle of Vimy Ridge was one of the opening battles in a larger British campaign known as the Battle of Arras. It is also considered a seminal event in Canadian history for the primary role that nation's forces played in the attack.
Vimy, located in northern France, was one of the most heavily defended points on the entire Western Front and was thought to be an impregnable fortress. The Germans had fortified it with tunnels, three rows of trenches behind barbed wire, and numerous machine gun nests. The French and British had suffered thousands of casualties in previous attempts to take the Ridge; the French alone lost 150,000 men at Vimy Ridge in 1915. The ridge, stretching from the town of Vimy to Givenchy-en-Gohelle, was a crucial point that allowed the Germans to control much of the surrounding territory. The ridge was the only major barrier keeping the allies from the wide open Lens-Douai plain.
The Allied commanders decided to launch another assault in 1917. The duty was given to the still relatively fresh, but previously successful, Canadians. For the first time the four divisions of the Canadian Corps were brought together. They were joined by the British 5th Infantry Division.
The Canadian Corps' commanders were determined to learn from the mistakes of the French and British and spent months planning their attack. They built a replica of the Ridge behind their own lines, and trained using platoon-level tactics, including issuing detailed maps to ordinary soldiers rather than officers or NCOs alone. Each platoon was given a specific task by their commanding officers, rather than vague instructions from an absent general. They also employed older techniques such as the detonation of large mines under the German trenches.
On April 2, 1917, the Canadian Corps launched the largest artillery barrage in history up to that point. They shelled the German trenches for the next week, using over one million shells. The attack was loud enough that it could be heard in London. At dawn on Easter Monday, April 9, the 30,000-strong Canadian Corps began the attack, using a creeping barrage, a new technique whereby soldiers walked across no-man's land just behind a continuous line of shells (an improvement over previous battles, in which both sides had often shelled their own troops). Several new and untested methods of counter-battery fire were also used successfully at the start of the battle. This disabled a large portion of the German artillery for the infantry. After less than two hours, three of the four Canadian divisions had taken their objectives; the fourth division, however, was caught by machine gun nests on the highest point of the Ridge known as Hill 145. The 87th Battalion suffered 50% casualties. The 85th Nova Scotia Highlanders, who had been intended to be in a supply and construction role, were sent into the battle and the division captured the hill by the end of the day.
It is said that upon learning of the victory, a French soldier replied, "C'est impossible!" ("It's impossible!"), and upon learning it was the Canadians who won, changed his answer to, "Ah! les canadiens! C'est possible!" ("Ah! The Canadians! It is possible!").
http://en.wikipedia.org/wiki/Vimy_ridge
With General Julian Byng, Currie was largely responsible for the tactics and careful planning which led to an unexpected triumph by Canadian forces at the Battle of Vimy Ridge in April, 1917. One of the most useful innovations introduced at this battle was the creeping barrage, which consisted of troops walking just behind an advancing line of shell fire from Canadian artillery, shielding soldiers as they approached the Germans. In addition, constant practice and new troop organization in which each platoon member was trained to carry out all platoon responsibilities, briefing of the frontline troops, the use of counter-battery fire measures and constant patrolling of the enemy defenses all contributed to the effectiveness of the Canadian army at Vimy and for the rest of the War. Currie and the Canadian Corps were successful again at Passchendaele (the Third Battle of Ypres) in November, but at the cost of 16,000 men. Currie had accurately predicted these high casualty figures when Haig ordered his troops to attack.
http://en.wikipedia.org/wiki/Arthur_Currie
