The Gran Chaco (chaco, derived from Quechua, means "hunting land") is an arid alluvial plain in the lowlands of south-central South America. Approximately 725,000 square kilometers in area, it lies between the Andes in the west and the Paraguay and Paraná rivers in the east, and between the Mato Grosso to the north and the Pampas to the south. The scrub forests and grasslands of the Gran Chaco, though sparsely populated, were the home of numerous indigenous groups. In the main they were hunters, fishers, and gatherers, moving seasonally in search of food and practicing supplementary farming. Few still follow their traditional way of life.

The religion of the indigenous groups of the Gran Chaco can be understood through an examination of their mythic narratives, which contain their primary structures of meaning. These myths give an account of a primordial time...