nearly ten o'clock
Napoleon had made up his mind that after Ligny the Prussians would retreat toward Namur , and sent Grouchy in pursuit of them along that road . That officer had gone many miles before he discovered the route they had really taken , and only came up with the rear of their column at Wavre on the morning of Waterloo . Blucher left one division to oppose him , and marched with the other three to join Wellington . It was not until nearly ten o'clock that the French attack began ; then a column moved down from the heights of La Belle Alliance against the wood of Hougoumont , and as it approached the leading companies broke up into skirmishing order . As these arrived within musketry range a scattering fire broke out from the hedges in front of the wood , and the battle of Waterloo had begun . Soon from the high ground behind Hougoumont the batteries of artillery opened fire on the French column . Its skirmishers advanced bravely , and constantly reinforced , drove back the Hanoverian and Nassau riflemen in front of the wood .