Wellington got his wish, though while he was stuck in a square fending off Ney’s cavalry, he didn’t know it. Blucher kept his promise from the night before. Von Bulow’s IV Corps slammed into Lobau’s understrength corps at Plancenoit and D’Erlon was forced to commit much needed units to keep Zeiten’s I Corps from rolling up his flank. Furthermore, Napoleon had to commit part of his reserve just to stabilize the situation, the least senior battalions of his Imperial Guard, the Young Guard.
The Young Guard was part of Napoleon’s personal command, the Imperial Guard, and could only be committed by his own words. Despite their lack of seniority, the Young Guard were some of the best troops in Europe and temporarily checked the Prussians, but the fighting in Plancenoit was fierce. It was the reverse of Hougamont and La Haye Sainte with the French barricaded in the buildings and courtyards and is considered by most historians as the worst urban fighting of the Napoleonic Era. Just after 1800, Blucher paused his attack and began to reorganize for a final push.
At 1830, Maj Baring could no longer defend La Haye Sainte: his troops were out of ammunition. They had fired everything they brought, everything they were given, and everything they could scrounge. D’Erlon finally threw them out. At 1850, the nimble horse artillery batteries began to pound Wellington’s vulnerable squares from near point blank range and soon they were joined by the big guns from the Grand Battery. It was at this point the mounted Earl of Uxbridge approached the Duke of Wellington and just that moment a cannon ball took his leg. Completely unperturbed, he said,
“By God, Sir, I’ve lost my leg.”
The Duke coolly replied, “By God, sir, so you have.”
Despite the pounding the Allies were receiving, the Prussian attack, Baring’s defense, and six hours of near constant fighting severely depleted D’Erlon’s Corps. Moreover, a reformed Dutch brigade attempted to retake La Haye Sainte. Even worse Wellington reformed most of his men back into lines. D’Erlon would need more men to even attempt to break through. And he needed them ricky tick: the Prussians renewed their attack on Plancenoit at 1900 with the near assurance of quick victory, and the French artillery was almost out of ammunition.
After a personal inspection by Napoleon himself, the remainder of the Imperial Guard, the last uncommitted French troops, stepped off into the attack at 1930, 18 June, 1815.