well, the eagles music was somewhat of a blur on the charts...their early music had a kinda-sorta country-western type of sound to it. understandable, as the eagles started life as linda ronstadt's back up band; HER early music had a definate folk/country sound to it.
the eagles early stuff sounds very close to what is now called "country pop", similar to what alan jackson, kenny chesney, dwight yochum and others are doing now.
later on in their career, the eagles aquired a harder "edge" to their sound; but nowhere like the schreeching guitars and out of tune schreaming done by "guns 'n roses" and the other acid rock bands who used loud volume, synthesized soundtracks and bellowing vocals to cover up the fact that their hair and make up was done better than their music was.
"rock" is a rather broad term for modern music, isn't it!