This work offers a wide-ranging survey of natural and moral observations about the Americas, describing indigenous religions, rites, temples, priests, and sacrifices including human offerings; cataloging superstitions, funerary practices, and ceremonies that sometimes parallel Christian sacraments; and analyzing political institutions, calendars, writing and record-keeping, laws, architecture, economic organization, and communication systems among various peoples such as the Mexica and the Incas. The author balances ethnographic description with reflections on how knowledge of local customs might inform evangelization and governance, and frequently compares American practices with classical and Old World precedents.