The modern American holiday of Mother’s Day was first celebrated in
1908, when Anna Jarvis held a memorial for her mother in Grafton,
West Virginia.  Her campaign to make "Mother’s Day" a recognized
holiday in the United States began in 1905, the year her beloved
mother, Ann Reeves Jarvis, died.

Cinco de Mayo (Spanish for "fifth of May") is observed to commemorate
the Mexican army‘s victory over French forces at the Battle of Puebla 
on May 5, 1862.