Cocoa trees originated in South America's river valleys, and, by the seventh century A.D., the Mayan Indians had brought them north into Mexico. In addition to the Mayans, many other Central American Indians, including the Aztecs and the Toltecs, seem to have cultivated cocoa trees, and the words "chocolate" and "cocoa" both derive from the Aztec language. When Cortez, Pizarro, and other Spanish explorers arrived in Central America in the fifteenth century, they noted that cocoa beans were used as currency and that the upper class of the native populations drank cacahuatl, a frothy beverage consisting of roasted cocoa beans blended with red pepper, vanilla, and water.