In September 1915 the British Army had launched its attack against the German lines at Loos-en-Gohelle in support of a French assault on Vimy Ridge. Times and positions had changed and in April 1917 it would be the turn of the British that made the attempt on this important feature to the north west of Arras.
The ridge protected the German occupied positions controlling the mining area around Lens which was supplying Germany with much needed coal. It also formed an important stronghold along the main German defensive system: The Hindenburg Line.
The French intended to launch an assault in the area of the Chemin des Dames and and as part of General Robert Nivelle's overall plan he required General Haig to launch his 1st and 3rd Armies against the Germans to the east and north of Arras.
Nivelle was utterly convinced that he had a winning formula and had managed to convince both governments to go along with his ideas -despite some misgivings.
In May 1915 the French had managed to storm the ridge and the Moroccan Division (which included part of the famous Foreign Legion) had for elusive hours held the heights. Without reserves immediately to hand, they were forced to retire.
In early 1915 the generals were still learning, and one thing that they were learning fast was the fact that without artillery to subdue the enemy machine gunners and destroy his emplacements, advancing infantry were invariably marching to their doom. No amount of bravery, leadership, or élan made soldiers impermeable to bullets.
They had also started to learn that reserves were of no use if they were situated hours behind the front lines which had been part of the failing for the French at Vimy in May 1915 and the British at Loos in September 1915.French offensives: 1915
The task of taking Vimy Ridge fell to the Canadians who would have all four of their Divisions fighting side by side for the first time.
Their commander: Lieutenant General Julian Byng had a seven kilometre front to assault, including Hill 145 which rose 61 metres above the start line.
The Germans had been in possession of the ridge for two years and had made the most of it. Deep bunkers could shelter thousands of troops from any bombardment whilst their trench system had been fortified with concrete pill boxes concealing machine gun positions.
The Canadians for their part arrived in late 1916 following their ordeals on the Somme. In front of them was a lot of hard work and labour during the coldest winter of the war.
Training was the watchword. If intelligence could be gained about the enemy positions and units, if the topography could be recreated for training purposes, and if every man in those assaulting waves knew his exact task and what was required of him: victory would follow.
This was not a Canadian invention, the French planning in 1915 had been very similar and the British were working on the same principles in their planning for the attack against Messines in June 1917. It was more a case of having well organised Generals backed by an excellent administrative staff. It was also a case of having artillery and reserves readily at hand.
In carrying out intelligence gathering raids into the German lines the Canadians lost 1,400 men over a space of three weeks in the run up to the battle, but what was learnt was to bear fruit on 9 April.
Behind the lines Canadian soldiers practised on terrain similar to the ridge, following guide tapes, in order to become familiar with possible obstacles and how to overcome them.
Chaps, you shall go over exactly like a railroad train, on time, or you shall be annihilated
Sir Julian Byng.
It is very easy to look at the ridge and think that all four Canadian Divisions had the same task, but this is far from the truth.
Try and think of two lines joined at the top, running north to south and north to south-east. The first represents the two front lines and the second Vimy Ridge.
The Canadians Divisions were formed up in numerical order from 1st Division in the south to the 4th in the north. 1st and 2nd Division had a lot of open ground to cover before they would pull up alongside the 3rd and 4th who were taking on the ridge itself.
The area of the trenches and tunnels that you can visit today fell within 3rd Division's area. The area surrounding the monument would be taken by the 4th.
Tunnels were an all important feature of the attack.
For years the French, British and Germans had been carrying out mining in the area, leaving a lunar landscape and the vestiges of numerous tunnels. These tunnels were extended by the Engineers to provide a system of delivering assaulting troops right into the heart of the battle.
Five kilometres of tunnels were built to shelter soldiers before the attack, some quite short others running to a kilometre in length. As you will see if you visit the Grange Tunnel on the site, they were equipped with water and electricity. Chambers were cut to provide space for Headquarters troops, communication points and dressing stations.
Above ground, roads were repaired and light railways built.
French failures in 1915 had been put down to the lack of artillery and the Canadians had no intention of being accused of the same failing.
Lessons had been learnt from the Battle of the Somme, where the greatest barrage ever put down by British Artillery had been found to be wanting on 1 July 1916.
The Canadians supported by British Artillery would employ thirty times more pieces of artillery than the French had used two years before. More than 350 heavy guns and 700 field guns would provide one heavy gun and two field guns for every 20 metres of front to be attacked.
One of the other problems at the Somme had been the lack of a shell fuse that was sensitive enough to explode on contact with barbed wire. The British had resorted to using shrapnel shells in the hope that the flying pieces of metal would cut the wire - often the shell went into the ground before exploding and the wire remained uncut.
A new, sensitive fuse, called a 106 had been introduced and this was just the trick for barbed wire entanglements.
On 20 March the preliminary bombardment began the process of firing a million shells into the German lines and supporting artillery positions.