The French army of 72,000 arrived on 17 June before the strong defensive positions taken by the allies, commanded by Wellington and numbering 68,000. Napoleon cancelled his attack plan until the following morning, to allow the sodden ground to dry out. The following day, 18 June, Napoleon delayed again, still waiting for the ground to dry. To compound Napoleon’s difficulties, Grouchy still had not found the retreating Prussians. Unknown to Napoleon, the Prussian commander von Blücher had rallied his battered army, re-formed and was marching westward to join Wellington’s army. On hearing this news, Wellington decided to stand his ground. In the hour or so before midday Napoleon deployed his army to maximum psychological effect where it could be seen in all its splendour by many units of the allied army. Out in front was the Grand Battery of 84 guns, aimed at the allied centre. Wellington had placed the majority of his units on the reverse slopes of a long low ridge, out of sight of the French artillery.
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