There's been a lot of talk in recent years about how Cinco de Mayo isn't a big Mexican holiday, not like the 4th of July is in the United States.

It's true.

A just-released book from UCLA professor David Hayes-Bautista, El Cinco de Mayo: An American Tradition, argues that Cinco's prominence in America isn't the result of just beer-company marketing.

It was a deliberate move on the part of Latinos in California:

Hayes-Bautista researched the origins of the holiday and found that, at the time the Mexicans were battling France in 1862, Latinos in California were worried about the U.S. Civil War making slavery a coast-to-coast practice that would ensnare all people of color.

He says it was a serious fear in California's Mexican-immigrant communities.