Historically, the native people of Guam venerated the bones of their ancestors, keeping the skulls in their houses in small baskets, and practicing incantations before them when it was desired to attain certain objects. During Spanish rule (1668–1898) the majority of the population was converted to Catholicism and religious festivities such as Easter and Christmas became widespread. Many CHamorus have Spanish surnames, although few of the inhabitants are themselves descended from the Spaniards. Instead, Spanish names and surnames became commonplace after their conversion to Catholicism and the imposition of the Catálogo alfabético de apellidos in Guam. Historically, the diet of the native inhabitants of Guam consisted of fish, fowl, rice, breadfruit, taro, yams, bananas, and coconuts used in a variety of dishes. Post-contact CHamoru cuisine is largely based on corn, and includes tortillas, tamales, atole, and chilaquiles, which are a clear influence from Mesoamerica, principally Mexico, from Spanish trade with Asia.