Gonzalo Mendez was born in Mexico in 1913. Mendez, his mother, and her other four children moved to Westminster, California, in 1919. In 1943, at age 30, he became a naturalized citizen of the United States and was a relatively well-off vegetable farmer. By this time, Mendez and his wife had three children who grew up speaking English as well as Spanish, and in fact, the family spoke more English than they did Spanish when at home. In the neighborhood where the Mendez family lived, there was only one other Mexican-American family. The other neighbors were all Anglos, and all of their children attended Westminster Main School.
In 1945, when his children went to register for school, Gonzalo expected that they would be attending Westminster Main School, the same school that he had attended with other Mexican and Anglo children until he was forced to drop out to help support his family. Much to his surprise, when his children returned home, they informed him that they would have to attend the Hoover School, which was located in a different school district, and furthermore, all of the students there were Mexican or Mexican-American. Gonzalo spoke with the principal, the Westminster School Board, and eventually the Orange County School Board, but without success.
With the aid of his lawyer, Gonzalo discovered that other school districts in Orange County also segregated their Mexican-American students. On March 2, 1945, the attorney representing Mendez and the other plaintiffs filed a class action suit in a U.S. District Court not only on their behalf but also on behalf of some 5,000 other persons of “Mexican and Latin descent.” The defendants were four school districts, their superintendents, and their school boards. The plaintiffs argued that their children had been arbitrarily assigned to attend schools “reserved for and attended solely and exclusively by children … of Mexican and Latin descent” while other schools in the same system were “reserved solely and exclusively for children known as white or Anglo-Saxon children.” When there was no state law mandating their segregation, they argued that segregating children of Mexican ancestry was a violation of the equal protection of the law clause of the Fourteenth Amendment. The attorney did not argue that the school districts were segregating on the basis of race. In fact, he argued, there was no “racial” segregation because “Mexicans were members of the white race.” The attorney knew that he could not argue that segregation based on race was unconstitutional because the U.S. Supreme Court in Plessy v. Ferguson in 1896 had upheld racial segregation. The case was assigned to U.S. District Court Judge Paul McCormick of the Southern District of California, Central Division.