Duchy of Sora

The Duchy of Sora was a semi-independent state in Italy, created in 1443 by King Alfonso I of Naples and dissolved in 1796. It occupied the south-eastern part of what is today Lazio, bordering what is now Abruzzo. Its capital was first Sora, later, under the Boncompagni family, Isola di Sora.

The County of Sora had been constituted in 1399 as a fief of the Kingdom of Naples. In 1443 Nicola Cantelmo, who was already count of Sora and nearby Alvito, was named the first duke of Sora by Alfonso I. His fief was intended as a buffer between the Neapolitan kingdom and the Papal States. The Cantelmi struggled in the 15th century for a greater degree of autonomy, often taking advantage of the succession crises that threatened to tear apart the Kingdom of Naples until the early 16th century.

In 1450, during one of these wars, Pope Pius II, who supported the Aragonese party, sent Federico III da Montefeltro against the Cantelmi. The Soran army was defeated and the duchy pacified. In 1463 however the Cantelmi rebelled again. This time the papal commander was Napoleone Orsini, who captured Isola del Liri, Arpino, and a large piece of territory, making Sora a papal fief. Piergiampaolo Cantelmo lost the ducal title. His remaining lands in Alvito and Popoli were assigned to his brother Giovanni Cantelmo with the title of Count. In 1472 Pope Sixtus IV renounced his feudal rights over Sora: the duchy of Sora, now separated from that of Alvito and augmented by the addition of Arce, was given to his nephew Leonardo della Rovere, who married a daughter of King Ferdinand I of Naples.

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