Día de los Muertos, or “Day of the Dead,” is a popular celebration in Latin America. Despite the title being in the singular, the celebration usually lasts two days (November 1 and 2). While it is not a Catholic celebration, most Catholics celebrate it in the areas of the world where it is popular. The fact that it is not technically a religious holiday does not deprive it of meaning. After all, Memorial Day in the United States is not a liturgical holiday, but attending Mass and visiting graves of veterans is certainly a pious and commendable thing to do on that day.
Because its origins are non-Christian, not every custom or tradition of the day will be acceptable. It is believed to have been celebrated originally in the summer by the Aztecs, but when the culture became Catholic, it was moved to coincide with All Souls and All Saints Days. Catholics have usually celebrated the feast by having family meals at the graves of loved ones, decorating altars of prayer in their homes with pictures of deceased family, and having communal meals with neighbors, friends and family. The essence of Catholic celebration of this feast has been an emphasis on the Communion of Saints, that we are all still connected to each other both in this world and the next.
Another popular activity is painting faces to look like skulls, but it is important to note that the meaning behind this is not the same as Halloween. On Halloween, a skull is meant to be creepy, scary, or funny. For Día de los Muertos, it is actually considered reverent. Part of this tradition comes from the image of La Catrina, which has a long history of being used in satire, social commentary, and cultural imagery.
The main reason, though, is that Día de los Muertos is meant to embrace death as part of the cycle of life and as something that need not be feared. Death is embraced almost like any other milestone in life. The skull face painting is seen as normalizing death and stands in complete opposition to the themes of Halloween.
So long as the elements of celebrating Día de los Muertos do not contradict our faith or blur the essentials of our faith, there is nothing wrong with Catholics celebrating it. In my personal opinion, the more I read about the feast, the more I wish Catholics in the United States would celebrate this instead of Halloween!