Duchy of Naxos

Also known as Duchy of the Archipelago, Duchy of the Aegean

The Venetian-Cycladic duchy founded by Marco Sanudo in the wake of the Fourth Crusade — a maritime principality of two dozen Aegean islands, the longest-lived Frankish state of all.

The Duchy of the Archipelago was founded by Marco Sanudo, a great-nephew of Doge Enrico Dandolo of Venice, in 1207 — three years after the Fourth Crusade. Sanudo equipped his own ships, fought his way into the central Aegean, and seized Naxos and the surrounding islands for himself; the Venetian state did not officially endorse his conquest, but it tolerated and ultimately benefited from a private duchy of Cycladic waters.

The Sanudi ruled twenty-one islands from a remarkable Frankish fortress on Naxos itself, with subordinate lordships scattered from Andros and Tinos in the north to Santorini and Anaphi in the south. Successive dukes wove a careful diplomatic web among Venice, the Latin Empire, the Byzantine successor states, and the Crusader Kingdom of Cyprus. The duchy passed by marriage to the Crispo family of Verona in 1383, who continued the Frankish rule in essentially the same form.

Decline came with the Ottoman advance in the central Aegean. The duchy became an Ottoman vassal in 1537 and was repeatedly raided by Hayreddin Barbarossa; the Crispi were finally deposed in 1566. A short-lived Joseph Nasi tenure as duke under Ottoman appointment ended in 1579, when the duchy was formally annexed to the Ottoman Empire — the very last Frankish state of the Latin East to disappear.

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