It was the Palace of the Rector or Governor of the old Republic of Ragusa. 

In the fifteenth century it was rebuilt with a mix of Gothic and Renaissance styles, probably because of 2 big explosions, but after the earthquake of 1667, the palace was badly damaged and there was a new reform that gave him a style baroque.

It has a beautiful gallery with arches and carved capitals and a beautiful courtyard. On the first floor were the apartments of the rector, which today are part of a museum and home to a small art gallery with works from the sixteenth century and a large collection of coins, stamps and measures used in the Republic of Ragusa.