The Eagles were one of the most successful bands of the 1970s. Not surprisingly, they got their start as session musicians who were put together by a Hollywood producer to play on Linda Ronstadt's Silk Purse album. The lineup then consisted of Don Henley, Glenn Frey, Randy Meisner, and Bernie Leadon (of Flying Burrito Brothers). Burrito bass player Chris Hillman (also of the Byrds) once stated in an interview for MOJO magazine that Frey and J.D. Souther, who co-wrote many of the Eagles' hit songs, would attend every FBB show and watch Gram Parsons as if they were studying him in order to write a thesis. Hillman opined that the Eagles went on to become a very successful, slick version of the Burritos. In that respect, listening to the Eagles' early recordings reveal that they seem to have borrowed Parsons' Cosmic American Music vision to invent a prosperous decade-long career. Their first self-titled album went gold in 1973 (shortly after Parsons died). Don Felder was added on as a fifth member of the band for their third album, On the Border. Then in 1976, when they lost Leadon, the band recruited Joe Walsh from the James Gang only months before releasing Hotel California. The album sold more than nine million copies. The Eagles continued to challenge themselves musically and physically until their split in 1981. Their commercialized Country Rock went through many different production hoops but always managed to boast some of the tightest and most melodic four-part vocal harmonies to ever grace the genre.