The countries I'm thinking about are England and Turkey (northwest and southeast). This type of alliance seems unlikely to develop "naturally" in the real world, since they're nowhere near each other, but they have a common enemy, Russia.
I have to assume that more pressing concerns for each are "taken care of" by "natural" rivalries, Italy vs. Austria, and Germany vs. France.
But if England and Turkey succeed in partitioning Russia, can they find "common ground" in a war against say, the Germanic countries, Germany and Austria-Hungary? Or possibly in alliances with them against the "Latins," Italy and France?