American Primitive Guitar began when John Fahey first composed and recorded avant-garde/neo-classical compositions using traditional country blues fingerpicking techniques, which had previously been used primarily to accompany vocals. Fahey was joined in the genre by Leo Kottke, Bob Hadley and Peter Lang throughout the 60s and 70s, all of whom played at one time or another on Fahey's Takoma Records label along with uncategorizable artists such as Robbie Basho. A good starting place to learn about Fahey and American Primitive guitar can be found on John Fahey's web page and on the John Fahey Wikipedia page.