Giudicato

The giudicati (judicatus in Latin; judicadu, logu or rennu in Sardinian) were independent states that took power in Sardinia between the ninth and fifteenth centuries. They were sovereign states with summa potestas, each ruled by a king called judge (judike in Sardinian).

After a relatively brief Vandal occupation (456-534), from 535 until the eighth century, Sardinia was a province of the Byzantine Empire.

After 705, with the rapid expansion of Islam, Muslim pirates from North Africa began to raid the island and encountered no effective opposition by the Byzantine army. In 815, Sardinian ambassadors required military assistance from the Holy Roman Emperor Louis the Pious.

In 807, 810-812, and 821-822 the Arabs of Spain and North Africa tried to invade the island but the Sardinians resisted several attacks. This defence was so effective that in a letter in 851, Pope Leo IV asked the Iudex Provinciae (judge of the province) of Sardinia, based in Caralis, for aid in the defense of Rome. With the fall of the Exarchate of Africa, based in Carthage, in the eighth century, and especially with the emergence of the Arab presence in Sicily (827), Sardinia remained disconnected from Byzantium and had, out of necessity, become economically and militarily independent.

The almost total absence of historical sources does not allow certainty surrounding the date of the passage from Byzantine central authority to self-government in Sardinia. It is believed that at some point the Iudex Provinciae, perhaps the praeses, of Caralis had complete control of the island. He appointed, in the most strategic area for the defense of the coast, the lociservator (lieutenant) who became substantially autonomous from Caralis over time; this was probably the action that precipitated the birth of the giudicati.

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