In the 1300s, a small band of violent, religious radicals called the Aztecs began minor raids throughout the area. Eventually they began to claim connections with the Toltec civilization, and insisted they were the rightful successors. They began to grow in numbers and conquer large areas of land. Fundamental to their conquest, was the use of political terror in the sense that the Aztec leaders and priests would command the human sacrifice of their subjugated people as means of humility and coercion. Most of the Mesoamerican region would eventually fall under the Aztec Empire. On the Yucatán Peninsula most of the Mayan People continued to be independent of the Aztecs but their traditional civilization declined. Aztec developments expanded cultivation, applying the use of chinampas, irrigation, and terrace agriculture; important crops included maize, sweet potatoes, and avocados.