The Moratorium began as a peaceful protest against the growing death toll of Mexican-American soldiers in the Vietnam War.
In 1970, it turned deadly as sheriff's deputies cracked down on the crowd.
Several people died, including Los Angeles Times journalist Ruben Salazar.
Every year, the rally is held in a park named after him.
An activist and war veteran relived those moments in the rallies.
"Before I got discharged I was already opposed to the war and was angry about it," said Cruz Becerra. "It is part of our history. We took a stand against an unjust war and that mattered."
The activism continues.
For Chicanos, the fight for equality isn't over.
LA artists commemorate 50th anniversary of Chicano Moratorium with mural in East LA