A year after the Infante Henry the Navigator signed a charter on 21 March 1450 in Silves to pass the donatorio of the island to the Flemish nobleman Jacome de Bruges, the nobleman made for Terceira, where he disembarked along the southeast shoreline of the island, in an area called Pesqueiro dos Meninos.
But, as Francisco Ferreira Drummond later indicated, "that they established themselves a league away, on a vast and appreciable field, that they called Porta Alegre, constructing a small church to the invocation of Santa Ana, the first and only church on the island, where were annexed the chapels of Santo António do Porto Judeu and São Pedro da Ribeirinha...".
Drummond later added that these early settlers moved so far to avoid impending conflicts with Spain, in which Portugal was commonly active.
This areas was the oldest demographic centre by the time that Jácome de Bruges left Porta Alegre in 1456 to launch another settlement in Praia.
The discovery of a marble slab with inscriptions by Drummond and local inhabitants in 1780 imply that the parochial church of São Sebastião was established in 1480.