January 6th is Three Kings Day in Mexico, known as the Día de Reyes. This is Epiphany on the church calendar, the 12th day after Christmas, when the Magi arrived bearing gifts for baby Jesus. In Mexico children receive gifts on this day, brought by the three kings, los Reyes Magos, Melchor, Gaspar, and Baltazar. Some children receive gifts from both Santa Claus and the Kings, but Santa is seen as an imported custom, and the traditional day for Mexican children to receive gifts is January 6.
In the days preceding Kings Day children write letters to the Magi requesting a toy or gift that they would like. On the night of January 5th, the figures of the Wise Men are placed in the nativity scene. Traditionally children would leave out their shoes with a bit of hay in them to feed the animals of the Magi (they are often shown with a camel). When the children would wake up in the morning their gifts appeared in place of the hay. Nowadays, like Santa Claus, the Kings tend to place their gifts under the Christmas tree.
On Kings Day it is customary to eat Rosca de Reyes, a sweet bread shaped like a wreath, with candied fruit on top, and a figurine of a baby Jesus baked inside. The person who finds the figurine is expected to host a party on Día de la Candelaria (Candlemas), celebrated on February 2nd, when tamales are eaten.
A recipe for Rosca de Reyes from About.com's Guide to Mexican Food.
