Since the end of the Roman Empire that existed a Jewish minority in the territory that later became Portugal.
At the founding of the nation, in 1143, this minority was already widespread in some important locations as Santarém who had the oldest national synagogue.
The Jewish population increased favored by the necessity that the first kings (12th century) felt to populate the territory which was being conquered from the Moors.

In all places where the number of Jews exceeded the ten was created a community whose organizational center was the synagogue. Its bell called the faithful not only to prayer but also to provide them with any information coming from the king or any decision of the chief rabbi. The synagogue was the seat of community government.
In the 13th century, D. Afonso regulates the relations between Christians and Jews as they were beginning to create difficulties for the minority. This means that: Jews could not have Christian servants under penalty of heritage loss; any Jewish converted to Christianity that return to the original religion could be sentenced to death; Jews could not occupy official positions so that Christians would not feel hurt.

At the time of D. Dinis each community had one or more Jewish quarters. In that time, the chief rabbi had men, called ombudsmen, in major Jewish centers in the country: Porto (Region of “Entre Douro e Minho”); Torre de Moncorvo (“Trás-os-Montes”); Viseu (“Beira”); Covilhã (“Beira”/”Serra da Estrela”); Santarém (“Estremadura”); Évora (“Alentejo”) e Faro (“Algarve”). Those ombudsmen exercised true jurisdiction over all national Jewish communities.
The synagogue was a place so important of religious (as the church for Christians) and civil standpoint; was a meeting point for the community members.