Giovanni II Paleologo, Marquis of Monferrato, ordered the current castle to be built and work continued until 1357. When Casale assumed the role of capital of the Margraviate of Monferrato and obtained the title of city in 1474, it also changed castle, seat of the court, after the restoration with the marquises Guglielmo VIII (1464-1483) and Bonifacio V (1483-1494). When Giovanni II Paleologo died, the Gonzaga of Mantova took control of Casale. The castle was strengthened by new military techniques, so the walls and the plan shape were adjusted so that it became hexagonal (which we can still see today). The towers were also strengthened and four new ravelins were added. At the beginning of the seventeenth century, the castle returned to its role as the seat of the court. The Dukes of Mantova, who were busy negotiating with Savoia, stayed there. Later it became the principality of Duke Carlo II Gonzaga-Nevers (1637-1665), who holidayed there many times with his entire court, which gave a boost to the cultural life in Casale. Due to the crisis of the Gonzaga dynasty, the castle was on the verge of decline. The city fell to Savoia in 1708 and the castle became a barracks. In the mid-19th century, Casale was fortified in preparation for a war against Austria and the castle became a defensive structure. The eastern ravelin was demolished, creating the current Piazza Castello, which became an open-air market zone. With the unification of Italy, the other three ravelins were also demolished.