Juan de Plasencia was a Spanish Franciscan missionary born in 1520 in Plasencia, Spain who came to the Philippines in 1577. He documented his observations of the customs of the Tagalog people, including their social class structure and system of governance. He wrote two important works: The Doctrina Cristiana, one of the earliest books printed in the Philippines, and The Customs of Tagalogs, which described the Tagalog social classes as nobles/maharlikas, commoners/aliping namamahay, and slaves/aliping sa guiguilar. The basic unit of government was the barangay led by a chieftain, and disputes were settled by the chieftain