Napoleon had forced the Allies back at Quatre Bras. He captured their position at La Haye Sainte. He perceived that the strategic key to the whole field of battle was the hill crowned by the old stone _château_ of Hugomont. If that could be taken, Napoleon would be able to attack and turn Wellington's right flank. That accomplished, a junction of Blücher and his Prussians with the English would be prevented; the forces of the Allies would be split in two, and Napoleon would in all probability defeat them in detail, according to his time-honored method. The emperor could easily have finished off the Austrians in their turn, as he planned to do; and the combined European attempt to oust him would have been frustrated. Thus the Corsican would have been, probably for so long as he lived, the master of France at the least, even if the checks he had already received had restricted his mastery of the rest of the continent. Knowing well that upon this cast his fate was staked, Napoleon hurled his best troops, under Prince Jerome, against the little old _château_ on the hill. Again and again they assaulted it. Twelve thousand men were launched against the half-dilapidated castle, which had been pierced with loopholes for the British riflemen. And now and here came the crucial incident whose importance was rated so high by Wellington. At a moment when the chief defence of the _château_ was entrusted to the Coldstream Guards, under Colonel James Macdonnel, the French were within a hair's breadth of taking it. They pushed against the gate of the castle, and had actually forced it open, when the Coldstream Guards charged out with their bayonets, forcing the advance rank of the French back a little. But the French were pouring up, and could no longer be held back at the point of the bayonet. It was at this instant, when a slight leeway had been gained, that Colonel Macdonnel and Sergeant Graham, under a galling fire from the French, stepped forward and with their own hands closed the _château_ gates, barricaded them, and thus enabled the troops to resume their fierce rifle fire from within. After this the French made many more assaults on the heavy gates, but could not force them open again. Wellington meanwhile commanded a general advance, following a fresh repulse of the French onset; and the French line was thrown into confusion. He knew that Blücher was now at hand--it was by this time half-past seven in the evening--to support him. Blücher, indeed, arrived, and attacked and crushed the broken French right, forcing Napoleon to retreat in disorder. Thus was completed the victory which the heroic defence of Hugomont had made possible.