Word for opposing sides in a war

What word would I use when describing two opposing sides in a war?

Assuming I want to refer to them in a manner similar to the following:

Comparing/contrasting the ____'s of the war.

Using opposing sides lacks eloquence in my opinion. I'm also open to rewording the above so that opposing sides is not needed.


Solution 1:

I like this one: belligerents.

Solution 2:

opponents

or

combatants

equally include both sides in any kind of, well, opposition.

Solution 3:

Adversaries is another option.