[1] Starting from the village of São Paulo dos Campos de Piratininga (now São Paulo) the Bandeirantes had explored most of what is now southeastern and southwestern Brazil, effectively taking advantage of the union of the Crowns of Portugal and Spain from 1580 to 1640 to incorporate all the former Spanish territories then west of the Tordesilhas Line.

The newcomers, called Emboabas, found an alternative, shorter route to the sea; the Caminho Novo das Minas dos Matos Gerais to São Sebastião do Rio de Janeiro on Guanabara Bay, bypassing and alienating the original discoverers.

São Sebastião (later shortened to its present name of Rio de Janeiro) became the capital city of the viceroyalty and later of the United Kingdom of Portugal, Brazil and the Algarves.

Originally the term referred to birds with feathered legs and as, unlike the Paulista pioneers, the outsiders always wore knee-high boots with their trousers tucked in, giving them the name.

[2] [3] [4] [5] Alternatively, according to the Dicionário Houaiss emboaba could be derived from the Tupi words mbo (do) and tab (hurt) meaning "those who invade or attack" and would be applied to a group rather than an individual.