This is source I found from another site, main source you can find in last paragraph
Something was changing on the picket lines of a grape strike in Delano, California, in 1965. Farm workers were standing up and demanding more rights in a way that would forever alter agricultural labor in the U.S. And there was also a new style of theater: Luis Valdez, one of 10 children in his family, and one who worked the fields by age 6, found himself on the picket lines as a performer with the first version of El Teatro Campesino. They performed short and improvised skits entirely in Spanish about the theme of the greed of capitalism, represented by the patron (boss) and the power of unified campesinos (farm workers).
Their goal was to convince scabs, new workers paid to replace those who were striking, to leave the fields and join the strike. In the second year of the strike, when United Farm Workers co-founder Cesar Chavez led supporters on a march of more than 200 miles from Delano to Sacramento, ETC followed the protesters, marking the troupe’s first tour.
The production budget was essentially nothing and the cast, composed of migrant farm workers supportive of the strike, were largely inexperienced in performance art. All ETC had was a borrowed flatbed truck that served as a stage – and a mission: to make their audience feel solidarity with the farm workers’ struggle through performance art.
Though Valdez and ETC lacked basic resources and a real theater early on, they learned and evolved, and fast. They performed at different picket lines throughout California for 25 nights in a row.
Similarly, Valdez’s El Teatro Campesino – now in its 52nd year and with a real physical theater in San Juan Bautista – and Valdez himself have evolved over the years.
The five-year-long Delano grape strike ended successfully, with an eventual contract between grape growers and the UFW. UFW co-founders Dolores Huerta and Chavez rose to prominence, and Valdez established himself and ETC as artists.
Chavez chose Valdez to be the master of ceremonies for rallies, and he also gained traction among more mainstream celebrities: ETC presented song and dance numbers for Robert F. Kennedy in Stockton and Sacramento during his presidential campaign and received invitations to perform their politically charged plays at venues throughout the country.
In 1977, Valdez was commissioned by the Mark Taper Forum in Los Angeles to write a play about Chicanos and the history of Los Angeles. Zoot Suit – a script based on the 1942 Sleepy Lagoon murder trial in which 17 Mexican youth were arrested on insufficient evidence and racial riots between Chicanos and whites followed – premiered in spring 1978. The two-week run sold out, and after Valdez produced another version, it ran for an entire year. In 1979, Zoot Suit made history by becoming the first Latino-written-and-directed play to premiere on Broadway.
After Broadway, Valdez ventured into Hollywood. He directed a film version of Zoot Suit in 1981 and in 1989 followed with the movie La Bamba, which tells the story of Chicano rock ‘n’ roll icon Ritchie Valens, who died in an airplane accident along with Buddy Holly.
Both films earned Golden Globe nominations for best musical picture.
Valdez is today recognized as one of America’s leading Chicano artists. He’s acquired a diverse list of honors, including a Peabody for a play he televised for PBS, the Aguila Azteca Award (Mexico’s highest honor to foreigners of the country), and a Presidential Medal of the Arts – twice (more on that later).
Most recently, Valdez can be heard in movie theaters as the voice of Tio Berto in Pixar’s latest film Coco. The acclaimed Día de los Muertos tale, which opened in Mexico in October and the U.S. in November, has already broken the record as the highest-grossing film released in Mexico.
Hollywood aside, Valdez’s home is still in San Juan Bautista. On a recent evening, the sun is setting on the small town as 77-year-old Valdez grabs a cup of coffee from the bar at El Teatro Campesino’s headquarters on Fourth Street. The den of this playhouse – formerly a warehouse for produce – is decorated with various artifacts: a framed portrait of Valdez in the early era of ETC with a UFW flag waving behind him, a multi-colored Aztec calendar used as a prop in a 1973 play, a box of Corn Flakes featuring the face of Cesar Chavez.
Reflecting on 50-plus years of ETC and his remarkable rise, Valdez spoke to the Weekly about the presence of Mexican culture in media today, producing plays by and for campesinos, and why the future of Chicanos is a hopeful one.