São Paulo is Brazil's largest and most economic city.
As of September 2012, an Assassin team was located in the city. Secretly, there was a double agent in the team who was leaking their position to the Templars, which forced them to delay their progress and find the spy. After having done so successfully, they cut off contact with the Assassin headquarters and presumably moved to another city.
Months later, on 2 December 2012, the Assassin Desmond Miles traveled to a stadium in the city to find a power source, in order to continue his journey in the Grand Temple, there he fought several Abstergo agents and Daniel Cross, from whom he took the power source after knocking the latter out. Desmond later escaped the stadium using the Metro.