The United Farm Workers of America were founded in 1962 by César Chávez and Dolores Huerta . This union changed from a workers' rights organization that helped workers get unemployment insurance to that of a union of farmworkers almost overnight, when the National Farm Workers Association went out on strike in support of the mostly Filipino farmworkers in Delano, California in 1965. The NFWA, soon renamed the United Farm Workers Organizing Committee and then the United Farm Workers, launched a boycott of table grapes that, after five years of struggle, finally won a contract with the major grape growers in California. The union then brought in thousands more lettuce workers in the Salinas and Imperial Valleys and orange workers in Florida employed by subsidiaries of Coca-Cola.

The union publicly adopted the principles of non-violence championed by Mahatma Gandhi and Dr. Martin Luther King, Jr. Chávez used fasts both as means of drawing public attention to the union's cause and to assert control over an often unruly union. However, it also resorted to both sabotage and violence, including such things as nail "stars" scattered over roadways and throughout crops to flatten tires, two-by-fours straddled off either side of vehicles running between rows of grapes destroying the crops, mobs blocking roads and crop rows, attacking people in their vehicles and other such violence typical of the 1930's union fights. These measures were used not only against large corporate growers in Tulare, and Kern Counties, California, but also against small "mom & pop" family farmers with less than 10 acres (40,000 m²) in places such as Parlier.

The union was poised to launch its next major campaign in the orange fields in 1973 when a deal between the International Brotherhood of Teamsters and the growers nearly destroyed it. The growers signed contracts giving the Teamsters the right to represent the workers who had been members of the UFW.

The UFW responded with strikes, lawsuits and boycotts. The union struggled to regain the members it had lost in the lettuce field; it never fully recovered its strength in grapes, due in some part to incompetent management of the hiring halls it had established that seemed to favor some workers over others.

The battles in the fields became violent, with a number of UFW members killed on the picket line. The violence led the state in 1975 to try to find a solution for these problems by creating an administrative agency, the Agricultural Labor Relations Board , to enforce a law modeled on the National Labor Relations Act that would channel these disputes into more peaceful forms.

When first formed, the ALRB was decidedly pro-UFW. Now, thirty years later, the union still works to organize California farm workers, but the ALRB has been a disappointment to the union, since it has often operated slowly, when it functions at all.