I believe it has to be one of these three. Or maybe even all of them at the same time.

1 The triple Entente, 2 The Allies or 3 The United Nations.

What is the first time someone used the name Allies to discribe England, France and friends? I just read somewhere there are two book from that time that use the word Allies but I want to find the first mention.

Do all countries that fight on that side use the same name?

EDIT: I found a postcard that has the word Allies on it. It's from 1916. I'll try to get a link to it up here soon.