Treaty of Sapienza

The Treaty of Sapienza was concluded in June 1209 between the Republic of Venice and the newly established Principality of Achaea, under Prince Geoffrey I of Villehardouin, concerning the partition of the Peloponnese (Morea) peninsula, conquered following the Fourth Crusade. By its terms, Venice, which had been accorded most of the Peloponnese in the Partitio Romaniae, recognized Villehardouin in possession of the entire peninsula except for the two forts of Modon and Coron, which came under Venetian control, and secured commercial and tax privileges in the Principality. The text of the treaty is also a valuable primary source for the early history of the Principality of Achaea.

Following the capture of Constantinople and the dissolution of the Byzantine Empire by the Fourth Crusade in 1204, the victorious Crusaders partitioned the Byzantine territories among them. The treaty of partition, the Partitio Romaniae, assigned most the Peloponnese or Morea peninsula in southern Greece to the Republic of Venice, except for the northeastern regions of Corinthia and Argolis. In the event, Venice neglected to immediately enforce her claims, and in the course of 1205, a few hundred Crusaders, led by William of Champlitte and Geoffrey of Villehardouin, began to conquer the region on their own account. The conquest was fairly rapid, and the most determined Greek resistance was broken at the Battle of the Olive Grove of Koundouros in late summer. Isolated fortresses like Monemvasia, or the inhabitants of the mountainous regions of Tsakonia and Taygetus, still resisted, but by the end of 1205, Champlitte had consolidated his position enough for Pope Innocent III to refer to him as "Prince of Achaea".

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