Arthur "Big Boy" Crudup (August 24, 1905 – March 28, 1974) was an American Delta blues singer, songwriter and guitarist. He is best known outside blues circles for his songs "That's All Right" (1946), "My Baby Left Me" and "So Glad You're Mine", later covered by Elvis Presley and other artists. 　　In 1968, the blues promoter Dick Waterman began fighting for Crudup's royalties and reached an agreement in which Crudup would be paid $60,000. However, Hill and Range Songs, from which he was supposed to get the royalties, refused to sign the legal papers at the last minute, because the company thought it could not lose more money in legal action. In the early 1970s, two Virginia activists, Celia Santiago and Margaret Carter, assisted him in an attempt to gain royalties he felt he was due, with little success. 　　On a 1970 trip to the United Kingdom, Crudup recorded "Roebuck Man" with local musicians. His last professional engagements were with Bonnie Raitt. 　　Crudup died in 1974, four years after the failed royalty settlement. There was some confusion about the date of death because of his use of several names, including those of his siblings. He died of complications of heart disease and diabetes in the Nassawadox hospital in Northampton County, Virginia, in March 1974. 　　Crudup has been honored with a marker on the Mississippi Blues Trail, placed at Forest. Elvis Presley acknowledged Crudup's importance to rock and roll when he said, "If I had any ambition, it was to be as good as Arthur Crudup".