Guaikuru

Guaycuru names nomadic Guaicuruan speakers of the Gran Chaco, such as the Mbayá. A Guaraní epithet meaning savage, it was first applied to the Mbayá; bands were matrilocal and never politically united. Sixteenth-century bands lived by hunting and gathering; the riverine Payaguá menaced Spanish river traffic for two hundred years.

After Cabeza de Vaca destroyed a Mbayá camp by Asunción in 1542, the Guaycuruans took to horses and formed a raiding culture: by the 1600s attacks forced Santa Fe's relocation; in 1735 Mocoví and Toba sacked settlements in Salta Province. Smallpox in 1732 to 1736 and Spanish encroachment broke their peak power.

In 1743 Jesuits opened the first lasting Mocoví reduction at San Javier; by the early 1780s five to six thousand lived in missions, many returning to nomadism. The early nineteenth-century independence wars split them: some served the new republics, others raided; much of the Chaco stayed theirs.