One of the largest buildings in Birgu is the Inquisitor’s Palace. Built originally by the Knights of the Order of St John soon after their arrival in 1530 as a Law Courts, the building started to be used as the Inquisitor’s Palace from 1574 onwards. The original building was small, and it was enlarged by piecemeal by the Inquisitors that came to Malta. The prison cells were also increased accordingly. The Palace was the Law Courts of the Holy Tribunal, but it was also the offices of the same tribunal, the prison, as well as the residence of the then Inquisitor. 

The present building dates to the 18^th century, when permission was granted to enlarge and provide the palace with a more aesthetic façade. The building was used by the British military personnel for a number of years before it was turned over to the Museums Department after the end of the First World War. The Dominican Friars made use of the palace as a temporary church and convent after their own buildings were destroyed during the Second World War. Today it is open as a Museum.