SOLVED. Science Fiction - Social Evolution, Feline Species, Twin Planets, "Shining Sister", Cultural Clash & War of Annihilation [s]

[Bargle]

I don't recognize the book, but here's a list of books with feline type characters.
http://anthrozine.com/site/lbry/cat.n...

[Michael]

I stro gly suspect that this book is H. Beam Piper's First Cycle. The plot matches spot-on. Take a look at the cover and see if it rings any bells.

[Paul]

YES, yes, thank you. It is First Cycle! I remember now that I had also read one of H. Beam Piper's Little Fuzzy books shortly before.

[Rosa]

Please don’t delete your first post.