Who is Chewbacca from The Last Command and what is their importance?

Chewbacca is a Wookiee: Chewbacca or "Chewie" remains in this novel Han Solo's partner and sworn protector for life, extending his oath to Solo's wife Leia Organa Solo and their newborn twins. Chewie is mechanically adept and keeps the Millennium Falcon running as smoothly as possible. He is a sure shot with the bowcaster.