<Li> Hundred Days <Ul> <Li> Amiens </Li> </Ul> </Li> <Ul> <Li> Amiens </Li> </Ul> <P> The Battle of Vimy Ridge was a military engagement fought primarily as part of the Battle of Arras, in the Nord - Pas - de-Calais region of France, during the First World War . The main combatants were the Canadian Corps, of four divisions, against three divisions of the German Sixth Army . The battle, which took place from 9 to 12 April 1917, was part of the opening phase of the British - led Battle of Arras, a diversionary attack for the French Nivelle Offensive . </P> <P> The objective of the Canadian Corps was to take control of the German - held high ground along an escarpment at the northernmost end of the Arras Offensive . This would ensure that the southern flank could advance without suffering German enfilade fire . Supported by a creeping barrage, the Canadian Corps captured most of the ridge during the first day of the attack . The village of Thélus fell during the second day of the attack, as did the crest of the ridge, once the Canadian Corps overcame a salient against considerable German resistance . The final objective, a fortified knoll located outside the village of Givenchy - en - Gohelle, fell to the Canadian Corps on 12 April . The German forces then retreated to the Oppy--Méricourt line . </P>

When did the battle of vimy ridge start
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