Today the home of César Chávez will be a designated a "national monument" by President Obama. He's in California for obvious reasons, but his itinerary takes him to a place called La Paz, which is where Chavez helped organize growers under the United Farm Workers movement. And it’s where his body was laid to rest when he died in 1993.

Chávez and his wife Dolores Huerta were pivotal in getting farmworkers organized in the 60s and early 70s. He taught them how to negotiate with farm owners for better pay and conditions. And his story is a remarkable one — but as with all heroes — complicated. The man and his achievements are examined in "Trampling Out the Vintage: Cesar Chavez and the Two Souls of the United Farm Workers," written by Frank Bardacke.

"The political clout that Chavez managed to mobilize for farm workers came from linking up the farm worker movement...with the national boycott movement." Before that time, the farm workers had really been "without allies in the United States," says Bardacke.

"The guest worker program, which had been in place for 25 years — a whole generation of people — brought contracted Mexican farm workers — to California and Texas primarily — to work on farms, and was designed to prevent them from building unions, and to keep wages artificially low." When the program ended om 1964, there was a new space to build a union for farm workers.

"I think the time was right," Bardacke says, citing the political environment of the mid 1960s as part of the reason the farm workers'  movement succeeded. "Here comes a farm worker movement that liberals can support."