The village of Mutum, Rio Gregório Yawanawá Indigenous Territory, State of Acre, Brazil, 2016. In the course of some 50 years, the Yawanawá have emerged from complete invisibility into a period of exuberant cultural activity, becoming a reference point for sustainable living and indigenous culture for travelers from all over the world. In 1970, there were just 120 of them, with rampant alcoholism and the resulting social and cultural breakdown, to the point where their language was about to disappear. They were pressured not to use their language in front of whites, mainly by the owners of the rubber plantations, who controlled the forests of Acre from the late 19th century. The plantation owners treated them as slaves and did not want the language to reveal the existence of native tribes who might claim ownership of the land. Another threat was posed by Evangelical missionaries who had enforced Christian worship and attacked traditional indigenous rites as "demonic." Biraci Brasil Yawanawá, better known as Bira, assumed leadership of the group in the early 1990s, expelled the missionaries, got rid of the bibles, reestablished teaching of the traditional language, and began encouraging study of the old myths and stories as a way to pass down the old people's knowledge and memories to the new generations. In three decades, the population has grown to about 1,200 people.