The Area on which raises Rio de Janeiro, was reached by Portuguese explorers during an expedition course, guided by the Italian Amerigo Vespucci, in January of 1501. As at the beginning the European thought that the Bay of Guanabara was in reality the delta of a river, it was therefore that they called it “Rio de Janeiro”.

The City was founded the 1st of March 1565, by the Portuguese cavalryman Estacio de Sa, who called it Sao Sebastio do Rio de Janeiro, in honour of King Sebastiano I of Portugal. For centuries the settling was commonly called Sao Sebastio, instead that with the actually more popular second part of the name. Often it became attacked from the pirates and in particularly by these enemies of Portugal, like the Dutch and the French. At the end of the XVI century, the Portuguese crown begins to consider the village like a strategic place for the transit Atlantic of the ships that travelled between Brazil, African colonials and Europe. There were build fortresses and constitute an alliance with the native tribe, for defending the settling of the invaders- the nearby Niteroi, for example, was grounded from a native chief for helping the defence.

The exact point where Rio was grounded is at the feet of the famous mountain Pan of sugar (Pao-de-Acùcar). Later, the whole City was moved in a palisade on a peak of a hill, imitating the Middle- Aged European strategic of defence of the fortressed castles. – since than the place was called Morro do Castelo (Hill of the Castle). Thus the City was developed from the actually centre in south and south west direction, an urban movement still to be find today.

Until the beginning of the XVIII century, the City was threatened or invaded by various pirates and buccaneers, above all from the French, like Jean-Francois Duclerc. Rène Duguay-Trouin, and Nicolas de Villegaignon. After the 1720, when the Portuguese found gold in the nearby Main City of Minas Gerais, Rio de Janeiro becomes a useful harbour for embarking the richness, rather than the more distant Salvador. During the 1763, the colonial administration of the Portuguese America will be transferred to Rio.
The City remains essential a colonial Capital until 1808, when the royal Portuguese family and great part of the nobles of Lisbon, escaping from the Napoleonic invasion of Portugal, are settling here. The Capital of the United becomes moved to Rio, that so becomes the only European Capital out of Europe.
As there was no space and no urban structures for accommodating hundreds of nobles, many habitants will be simply evicted from their houses.

When the prince Pedro declares the independence of Brazil in 1822, he decides to keep Rio de Janeiro as a Capital of his new Empire, and still the region of the City was loosing importance- economical and political, in comparisons of San Paolo.