Lisbon’s castle has been dedicated to Saint George since, probably, the mid-17th century and the days of the restoration of Portuguese independence.
However, the cult of Saint George is much older. It had been known of in Lisbon since the 12th century, possibly brought by crusaders from Northern Europe who were involved in the conquest of the city in 1147.
One of the first churches built after that date was dedicated to Saint George. Although it has not survived, it was located between the Cathedral and Portas do Sol, with references made to it from 1165 onwards.
The saint was invoked by the people of Lisbon during the defence of the city against the Castilians (August 1384) and in the most iconic battle ever to take place in Portugal: the Battle of Aljubarrota (14 August, 1385).
For these reasons, Saint George became the patron saint of the kingdom, the new dynasty of Avis and its first representative, John I.
It was only in the 18th century, and definitively from 1821, that the Brotherhood of Saint George moved to the church of Santa Cruz do Castelo, finally bringing it closer to the most important emblem dedicated to the saint in Lisbon: the castle.