Giudicato of Arborea
The Giudicato of Arborea (Italian: Giudicato di Arborea, Sardinian: Judicadu de Arbaree, English: Courts of Arborea), also called Regno di Arborea was one of the four independent, hereditary "Judicatures" (giudicati) or Courts into which the island of Sardinia was divided in the High Middle Ages. It occupied the central-west portion of the island, wedged between Logudoro to the north and east, Cagliari to the south and east, and the Mediterranean Sea to the west. To the north west and beyond Logudoro was located Gallura, with which Arborea had far less interaction. Arborea outlasted her neighbours, surviving well into the 15th century. The earliest known judicial seat was Tharros (Tarra). Giudicato of Arborea at the times of its maximum expansion occupied the whole island's territory, except the cities of Alghero and Cagliari.
In the early 9th century, when the Arabs and Berbers of North Africa became aggressive in expansion and piracy, the central authorities of the Byzantine Empire were unable to effectively defend or consistently govern the imperial province of Sardinia. The local Byzantine magistrates, entitled iudici, meaning "judges" were increasingly left to provide for administration and defense by themselves. Maintaining the traditional forms and patterns of the imperial bureaucracy, the island's iudicati, originally an administrative sub-division, had become autonomous states provinces ruled by iudices. By the 10th century, these districts (like the provinces administered by dux ("Duke") and comes ("Count") on mainland Europe) had become hereditary or rotated amongst a few most powerful clans.
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