Heard the radio report that today is the 200th anniversary of the Battle. They reported that 50,000 men were killed or wounded and 10,000 horses perished.
"Marshal Ney, mounted on his 5th horse of the day, led the advance."
Wikipedia has a could history but what is most impressive are the paintings of the Battle (clickable) with the article.
https://en.wikipedia.org/?title=Battle_of_Waterloo
The horse of the Duke of Wellington
https://en.wikipedia.org/wiki/Copenhagen_(horse)
Napoleon's horse
https://en.wikipedia.org/wiki/Marengo_(horse)
It seems that the French Lancers were effective enough though defeated that the English converted their heavy cavalry to Lancers in subsequent years.
Cheers,
Steve Haupt