I adopted an nine y/o who is now 11 and an 8 y/o. They come with thier own personalities and memories from previous owners. Give him time to get comfortable. But the best part is watching them gain confidence with you . They start looking at you with those loving little eyes or follow you just to be close. I would always rescue an older dog now. Mostly because they need the love and they need the assurance that life will be easy for them from now on.
As I tytpe, my older one (Max) is snoring next to me and the younger one (Titus) is flipped on his back becomiong one with the couch.