The Carter family was made up of AP Carter, his wife Sara and Maybelle who was AP's sister in law. They started out singing gospel music but there pure simple harmony influenced many other family groups of '30s and '40s. There influence carried over into later years with musicians like Woody Guthrie, Bill Monroe, the Kingston Trio, Doc Watson, Bob Dylan, and Emmylou Harris. Bill Monroe is said to have derived his bluegrass style music from the Carter family.My personel opinion is that Bill Monroe derived Bluegrass from the mountain music that was played by the Carters throughout the Virginia and Tennesee hills. Some of the hits they had were "Will the circle be unbroken", "Wildwood flower", "Keep the sunnyside up" and "Wabash Cannonball". "Will the circle be unbroken" is one of the most inspiring songs i have ever heard. It will always be one of my favorites.