Napoleon had sent letters to the monarchs of Europe requesting peace, and they were returned unopened or destroyed. It was the other countries who sent the troops after Napoleon, not the other way around.
If Hitler had asked for peace in September 44, could the allies be considered in anyway at fault if they refused. If Nappy got peace he would have used the time to rebuild the French army. Then he would a have found a use for it, he was a warmonger . He had to be stopped to avert another European war.
If Blucher wasn't coming there would have been no battle. Wellington had no intention of fighting the most complete French army since 1812 with raw recruits and half his allies of doubtful loyalty. He would have retreated to Brussels and evacuated by sea if the Prussian hadn't agreed to come.
At Waterloo in Belgium, Napoleon Bonaparte suffers defeat at the hands of the Duke of Wellington, bringing an end to the Napoleonic era of European history.
At around 21:00 Wellington and Blücher met, signifying the end of the battle. Waterloo cost the Anglo-allied forces around 15,000 dead and wounded, and the Prussians some 7000. Napoleon lost 25,000 dead and injured. 8000 of his troops were taken prisoner.
After the French defeat at Waterloo and the final battle of the Napoleonic Wars at the Battle of Wavre, Napoleon was deposed and remained at large for some time in France before surrendering to the British. He was subsequently exiled to Saint Helena, where he died in 1821.