Zack de La Rocha is one of the biggest and most well-respected names in alternative music, known equally for his militant political activism and passionate vocal delivery. In the '90s he rose to fame as frontman for Rage Against the Machine and used that pedestal as a catalyst to further his left-wing political beliefs.

To understand the motives for De La Rocha's vocal stylings, one must first trace back his philosophical roots. His story begins in Irvine, CA, as a Hispanic youth in an area, which, during the '70s and '80s, was one of the most white-bred areas of California. His mother was an Anthropology Ph.D. and his father, Belo de La Rocha, was a well-known muralist, famous for his paintings of Zapatista farmers. His parents separated at an early age and Zack de La Rocha split his time between his two parents. At age 13, his father had a nervous breakdown and subjected his son to extreme religious asceticism. Soon, he could no longer cope with his father's fanaticism and chose to move in with his mother full-time. Within a few years, De La Rocha began to express his feelings of anger and isolation by listening to hardcore punk music, including Minor Threat, Black Flag, and Bad Religion. Before long, he had joined his first high school band, Hardstance, where he contributed both guitars and vocals. This band later evolved into Inside Out, which would eventually release one album on Revelation Records in 1991. As he grew older, he strayed away from his rock influences and became increasingly affected by a stream of hip-hop artists, such as KRS-One and Run-D.M.C. This is about the time when he bumped into Tom Morello, a Harvard-educated political science major and kindred soul in socialist thought. The two clicked musically and intellectually and started a band together, which De La Rocha dubbed Rage Against the Machine. With a backdrop of heavy metal riffs and Tom Morello's clever distortion techniques, De La Rocha's hip-hop-tinged vocals singed with unparalleled intensity. It wasn't long before the two were on the main stage at Lollapalooza II and became one of the most politically volatile bands ever to receive extensive radio and MTV airtime.