As a young up and coming singer, Mick Jagger would imitate James Brown's smooth dance moves. Even today, if you look closely, you can see that he attempted to copy all of his moves. They first met at the Apollo Theater in Harlem. In the 70's, James Brown actually invted Jagger to dance on stage at the Apollo with him. The two would remain friends and see each other occassionally as their tours crossed paths over the years. The two would remain friends for over 40 years until "Mr. Brown" died in 2006.
Mick Jagger actually holds the rights to James Brown's catalog. An idea was sparked about making a documentary about Brown's life, using his music. This eventually grew into the creation of the 2014 feature film, "Get On Up," about James Brown. Mick Jacker served as the Executive Producer of this movie, teaming up with Producer Brian Grazer. Tate Taylor directed the film and Chadwick Boseman plays the part of James Brown.
Little known fact: The last time Mick Jagger saw James Brown alive, the two were attending each other's shows in Cleveland, Ohio.