Dia de los Muertos in Mexico – Origins
The Day of the Dead celebrations in Mexico are from Pre-Columbian origins. Rituals celebrating the deaths of ancestors have been observed by these civilizations perhaps for 2,500–3,000 years. In the pre-Hispanic era, skulls were commonly kept as trophies and displayed during the rituals to symbolize death and rebirth.
The festival that became the modern Day of the Dead celebration happened in the ninth month of the Aztec calendar, at the beginning of August and was celebrated for an entire month. The celebration was dedicated to the goddess known as the Lady of the Dead, Mictecacihuatl.
In most regions of Mexico, November 1 is to honor children and infants and deceased adults are honored on November 2. November first is usually referred to as Día de los Inocentes (Day of the Innocents) or Día de los Angelitos (Day of the Little Angels) and November second as Día de los Muertos (Day of the Dead).
Historian, Harley Owners Club, Kingwood, Texas Chapter
Carlos Miller, The Arizona Republic
Gerald Erichsen, About.com