On the northern slopes of the Vulture volcanic massif, in Basilicata, lies Melfi at an altitude of 530 metres, with a population of around 17,000. Positioned along the Via Appia, it overlooks southern Capitanata and the Terra di Bari. Founded by the Byzantines at the beginning of the 11th century, Melfi gained importance under Norman rule and came to be known as the “moral capital of the conquest of Apulia”, serving as the venue for key assemblies and synods. Alongside Venosa, Troia, and Salerno, it was one of the four ducales urbes of the Duchy of Apulia.

During the Norman-Swabian era, Melfi was the largest city in Basilicata, hosting communities of Amalfitan merchants and Jewish families. In 1153, King Roger II commissioned the bell tower of the cathedral in Melfi; with its sculpted lions—symbols of royal power—it was intended to urge the people towards obedience.

Frederick II frequently stayed in Melfi between 1230 and 1247. During the summer, when the Tavoliere plain became unbearably hot, the emperor often sought refuge here, enjoying the cool climate and the ideal surroundings for hunting. During his longest stay, from 26 May to 10 September 1231, the famous Constitutiones—commonly known as the Constitutions of Melfi—were drafted and promulgated. These represented a synthesis of the legal cultures of the Norman-Swabian period and became the legislative code of the Kingdom of Sicily.

Regarding the Castle, Frederick II reinforced the pre-existing Norman structure (which now houses the National Archaeological Museum) and added three new towers: the Marcangione Tower, the Tower of the Four Winds, and the small ‘Parvula’ turret.