The legendary musician associated with the phrase "Outlaw Country" is Willie Nelson. He, along with other artists like Waylon Jennings and Johnny Cash, helped define this genre in the 1970s. Outlaw Country is characterized by its rebellious attitude and blending of country and rock elements, challenging the polished Nashville sound. Nelson's distinctive style, poignant songwriting, and cultivation of an independent spirit resonated with fans and helped shape modern country music.