Cinco de Mayo festivities are taking place across the U.S. with music, tacos and tequila flowing. In the U.S., the date is seen as a celebration of Mexican American culture, stretching back to the 1800s in California. Festivities include parades, street food, mariachi competitions and folkloric ballet — some playing on stereotypes. In Mexico where it's designated a holiday, it marks the anniversary of the 1862 victory by Mexican troops over invading French forces at the Battle of Puebla. The day falls on a Monday this year, meaning many of the events happened over the weekend. Still, Monday offers history lessons and festivals to enjoy.