The 1960s saw several important changes in popular music, especially rock. Many of these changes took place through the British Invasion where bands such as The Beatles, The Who, and The Rolling Stones, became immensely popular and had a profound effect on American culture and music. These changes included the move from professionally composed songs to the singer-songwriter, and the understanding of popular music as an art, rather than a form of commerce or pure entertainment. These changes led to the rise of musical movements connected to political goals, such as the American Civil Rights Movement and the opposition to the Vietnam War. Rock was at the forefront of this change.