It's like the franco-prussian war and German unification just didn't happen!
Have you ever asked yourself why France was so willing to fight Germany?
Have you ever asked yourself why France was so willing to fight Germany?
The Crimean war caused close to 1 million casualties in 3 years.
https://en.m.wikipedia.org/wiki/Crimean_War
The war involved Second French Empire, British Empire, Russian Empire and the Ottoman Empire.
Perhaps there are other examples of major wars, but this one seems significant.
EDIT: Outside of Europe, consider the Taiping Rebellion, with the highest deaths estimates at 30 million (or even higher!). The British and French got involved as well.