The indispensable legacy of African-American culture on pop music as we know it, sing it, and dance to it is well-trodden turf. Not so much the powerful musical root systems of Native Americans. Catherine Bainbridge and Alfonso Maiorana’s fascinating documentary packs a lot of info, sobering sociocultural revelations, and stirring music into a revelatory two-hour journey, lined with commentary by famed musicians and music chroniclers. Jimi Hendrix, Robbie Robertson, and the band Redbone are celebrated rockers with Native ancestry, but earlier and later, history was being made and influenced by seminal Native American–blooded musicians — a hot list including seminal bluesman Charley Patton, the great protorock guitarist Link Wray (with his classic “Rumble”), jazz singer Mildred Bailey, folkies Buffy Sainte-Marie and Peter La Farge, guitarist Jessie Ed Davis, and metal drummer Randy Castillo. Rumble tells an important, too-little-told story with great power about the U.S.’s sonic foundations and their periphery.