Napoleon opened the attack at around 11.00 against Wellington’s right flank at Hougoumont, where fighting continued through the afternoon. At 11.50 the Grand Battery open fire (other sources state later times), aiming at the centre of the allied line, inflicting a large number of casualties on the allies. At about 13.00 Napoleon spotted dark-clad ranks moving towards him about four or five miles to his right. He instructed that a message be sent to Grouchy to attack this approaching force. Grouchy, following Napoleon’s previous orders, was pursuing the Prussian rearguard near Wavre and was now too far away to reach Waterloo in time. The first French infantry attacks, supported by D’Erlon’s corps on the left, began just after 13.00, aimed at La Haye Sainte where stubborn resistance met the French advance. The allies were slowly pushed back but held on, under great pressure. Around 16.00 Marshal Ney mistook the movement of wounded to the rear as the signs of an allied retreat and ordered a massive cavalry attack on the allied centre, which was beaten off by the allied infantry after savage close quarter combat. Now the Prussians were on the battlefield, and at about 16.30 they threatened Napoleon’s right flank to which he sent reinforcements. Meanwhile, with the fall of La Haye Sainte, the allied front was exposed and Napoleon now committed his elite Imperial Guard infantry. Unsupported by cavalry, they were faced with determined resistance and short-range cannon fire, while the Prussians attacked and outflanked the French right. As the Imperial Guard began to fall back under withering fire, Wellington gave the order for a general advance, and the French army collapsed. The battle had cost the allies 22,000 casualties the French around 30,000.
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