High Quality Content by WIKIPEDIA articles! The Tupi people (also known as Tupinambá) were one of the main ethnic groups of Brazilian indigenous people. Scholars believe they first settled in the Amazon rainforest, but 2,900 years ago they started to spread southward and gradually occupied the Atlantic coast.The Tupi people inhabited almost all of Brazil's coast when the Portuguese first arrived there. In 1500, their population was estimated at 1 million people, nearly the same population of Portugal at that time. They were divided into dozens of tribes, living in each tribe from 300 to 2,000 people. Examples of tribes are: Tupiniquim, Tupinambá, Potiguara, Tabajara, Caetés, Temiminó, Tamoios. The Tupi knew agriculture therefore exceed a Palaeolithic condition. They grew cassava, corn, sweet potatoes, beans, peanuts, tobacco, squash, cotton and many others.