The Guató are an indigenous ethnic group of people who live in Brazil, states of Mato Grosso and Mato Grosso do Sul. There were 370 individuals according to Funasa in 2008.
They used to occupy most of the south-western portion of the Pantanal, the largest marshland in the world. They also lived on islands of the Paraguay river. Their presence in the region was first documented during the 16th century when the first Spanish and Portuguese adventurers reached these remote territories.
The Guató were expelled from their territory between 1940 and 1950. As cattle ranchers invaded their territories, they moved to other parts of the Pantanal, or relocated to cities like Corumbá, where they lived in poverty. After 1950 these people were considered extinct, and indigenist organizations stopped sending aid and support. But in 1976, some missionaries managed to identify indians of the Guató group living in the outskirts of Corumbá, and these people began to slowly try to fight for their rights once again, striving to obtain support from the indigenist organizations. Of the once many indians who produced canoes in the Pantanal region, these are the only remaining.
The Guató language was for a long time considered an isolate language, not related to any other in the region. In 1970 there was a proposition which linked the language to the large, and somewhat hypothetic, Macro-Ge linguistic family.
Guato at socioambiental.org