Sinatra and Davis
This is a famous story between Sinatra and Davis. Apparently, the Sands Hotel and Casino refused service to Sammy Davis Jr. Frank Sinatra famously backed him up and made sure that they not only treated Davis with respect but also told Davis to invite other Black friends to dine with them. Despite the fact that Davis was the butt of the joke for his race, Sinatra did stand up for him when he needed to.
Their Movies
Not only were they famous musicians, they were actors as well. They ended up starring in the films Robin and the 7 Hoods, Sergeants 3, and, of course, Oceans 11.