Bernal Diaz del Castillo 
The Memoirs of the Conquistador [EPUB ebook] 

According to Wikipedia: ‘Bernal Díaz del Castillo (1492 – 1585) was a conquistador, who wrote an eyewitness account of the conquest of Mexico by the Spaniards for Hernán Cortés, himself serving as a rodelero under Cortés… In the book, Castillo describes the Conquest of the Aztecs, in which he describes the Indoamerican cultures predominant in Mexico at that time. He also gives accounts of the human sacrifices, cannibalism and idolatry that he witnessed first hand… As a reward for his service, Díaz was appointed governor of Santiago de los Caballeros, present-day Antigua Guatemala. He finished writing his history in 1568, almost fifty years after the events described, a work he had begun (probably in the mid-1550s)…’