Which of the following is an independent clause? early american writers were mostly men. although early american writers were mostly men.

The first sentence is complete, it is a sentence that can stand alone. The second one however, is NOT a complete thought. The second sentence needs more information to be a complete sentence. For example we could right..  Although early American writers were mostly men, women had their fair share of writing. So, all that being said, it is the second sentence. :)