It is particularly celebrated in Mexico where the day is a public holiday. Prior to Spanish colonization in the 16th century, the celebration took place at the beginning of summer. It was moved to October 31, November 1 and November 2 to coincide with the Roman Catholic triduum festival of Allhallowtide: All Saints' Eve, All Saints' Day, and All Souls' Day.[2][3] Traditions connected with the holiday include building private altars called ofrendas, honoring the deceased using sugar skulls, marigolds, and the favorite foods and beverages of the departed, and visiting graves with these as gifts. Visitors also leave possessions of the deceased at the graves.
Scholars trace the origins of the modern Mexican holiday to indigenous observances dating back hundreds of years and to an Aztec festival dedicated to the goddess Mictecacihuatl. The holiday has spread throughout the world, being absorbed within other deep traditions for honoring the dead. It happens to be a holiday that has become a national symbol and as such is taught (for educational purposes) in the nation's schools, but there are families who are more inclined to celebrate a traditional "All Saints Day" associated with the Catholic Church.