Editing Battle of Vimy Ridge (section)

===Tactics===
[[File:Plan of Attack Vimy Ridge.jpg|thumb|left|upright|The Canadian Corps plan of attack outlining the four coloured objective lines&nbsp;– Black, Red, Blue and Brown]]
In January 1917, three Canadian Corps officers accompanied other British and Dominion officers attending lectures by the French Army on their experiences during the Battle of Verdun.{{sfn|Brennan|2007|p=94}} The French counter-offensive devised by General [[Robert Nivelle]] had been one of a number of Allied successes of 1916. Following extensive rehearsal, eight French divisions had assaulted German positions in two waves along a {{cvt|6|mi|-1}} front. Supported by extremely powerful artillery, the French had recovered lost ground and inflicted severe casualties on five German divisions.{{sfn|Nicholson|1962|p=227}}

On their return from the lectures, the Canadian Corps staff officers produced a tactical analysis of the Verdun battles and delivered corps and divisional-level lectures to promote the primacy of artillery and stress the importance of harassing fire and company and platoon flexibility.{{sfn|Nicholson|1962|p=227}} The report of the [[1st Canadian Division]] commander, [[Arthur Currie]], highlighted the lessons he believed the Canadian Corps could learn from the experiences of the French.{{sfn|Humphries|2007|p=67}} The final plan for the assault on Vimy Ridge drew on the experience and tactical analysis of the officers who attended the Verdun lectures. The First Army commander, General [[Henry Horne, 1st Baron Horne|Henry Horne]] approved the plan on 5 March 1917.{{sfn|Brennan|2007|p=94}}

[[Image:Julian Byng (April 1917).jpg|upright|thumb|[[Julian Byng, 1st Viscount Byng of Vimy|Byng]] during the battle|alt=Julian Byng in a black and white chest high portrait with foliage behind him. Byng has a moustache and is wearing a general officer's uniform that consists of a tailored jacket adorned with brass buttons. The collar is embellished with additional decorations denoting rank and service branch. He is wearing a peaked cap featuring ornate insignia indicating his rank and unit affiliation.]]
The plan divided the Canadian Corps advance into four coloured objective lines. The attack would be made on a front of {{cvt|7000|yd|mi+km|0}}, with its centre opposite the village of [[Vimy]], to the east of the ridge.{{sfn|Nicholson|1962|p=245}} The first objective, the Black Line, was the German forward defensive position.{{sfn|Granatstein|2004|p=113}} The final objective of the northern flank was the Red Line, taking the highest point on the ridge, the fortified knoll known as the Pimple, la Folie Farm, the {{lang|de|Zwischen-Stellung}} (intermediate position) and the hamlet of Les Tilleuls. The southern two divisions were to achieve two more objectives, the Blue Line, encompassing the village of Thélus and the woods outside the village of Vimy and the Brown Line, which aimed at capturing {{lang|de|Zwölfer-Graben}} (Twelve Trench) and the German second position.{{sfnm|1a1=Granatstein|1y=2004|1p=113|2a1=Nicholson|2y=1962|2p=254}} The infantry would advance close to a [[Barrage (artillery)|creeping barrage]] by field guns, advancing in timed {{cvt|100|yd|-2|adj=on}} increments.{{sfn|Granatstein|2004|p=113}} The medium and heavy [[howitzer]]s would establish a series of standing barrages further ahead of the infantry against defensive positions.{{sfn|Nicholson|1962|p=249}}

The plan called for units to leapfrog as the advance progressed, to maintain momentum during the attack. The initial wave would capture and consolidate the Black Line and then push forward to the Red Line. The barrage would pause for reserve units to move up, then move forward with the units pushing beyond the Red Line to the Blue Line. Once the troops secured the Blue Line, advancing units would once again leapfrog them and capture the Brown Line. Conducted properly, the plan would leave the German forces little time to exit their deep dugouts and defend their positions against the infantry.{{sfn|Turner|2005|p=38}} If the corps maintained its schedule, the troops would advance as much as {{cvt|4000|yd|mi+km}} and have the majority of the ridge under control by 1:00{{spaces|thin}}pm on the first day.{{sfn|Nicholson|1962|p=248}}