“[Johnson] came from an area and a people that were poor, and he was among them, he was one of them,” says Vicente Ximenes, a friend and collaborator of García, who was eventually named by then-President Johnson as chairman of the Cabinet Committee on Mexican American Affairs. “He was always able to get 90 percent of the Mexican American vote ... but he never voted for civil rights as a congressman and as a senator. If he had, the racist constituency he had would have voted him out of office.”

That’s where García came in. The doctor founded the American G.I. Forum, a civil rights group composed of Mexican American and white non-Hispanic veterans, and used its growing membership to try and influence political issues, including Johnson’s social policies. The relationship between the doctor and ambitious politician was long-lasting and sometimes contentious. Still, says García’s daughter Wanda García, “I believe they respected each other. Johnson had a very strong knowledge of how Mexican Americans and minorities were treated.”

“García would constantly challenge Johnson as few people would,” adds Valadez, “and I think Johnson loved that in a way. He loved a good fight and strong personalities."

Thanks in part to García’s influence, Johnson eventually brought more Mexican Americans into the federal government than any other president in history. He also signed into law two landmark acts — the Civil Rights Act of 1964 and the Voting Rights Act of 1965 — and in his speech before Congress introducing the Civil Rights Act, Johnson specifically mentioned his experience teaching in the segregated Mexican American school, where he saw children often come to school without having eaten breakfast.

“Johnson gave a lot of good speeches, but very rarely did he inject a personal anecdote about his own life,” says Valadez. “This is one of the very few times he reveals something personal about himself.”

Ultimately, The Longoria Affair peeks into a hidden history that is just starting to emerge. Before César Chávez and the United Farm Workers became its standard bearers, the movement for Mexican American civil rights was spearheaded by Dr. Héctor García and his efforts.

“History has tended to discount Mexican Americans’ achievements,” says Wanda García. “Mexican Americans were not aware of their history because this information was omitted from history textbooks. We were made to feel inferior, and I think that’s why no one spoke out. But now things are changing, and we are fighting to get our history into the schoolbooks.”

Independent Lens offers The Longoria Affair free online in English November 10 – 16. The Spanish version of the film will be available November 11 – January 10, 2011.