The Greek revolt of 1566–1572 was a series of conflicts between Greek rebels and the Ottoman Empire during the early period of Ottoman rule in the region. Social tensions intensified at the end of the 16th century by the debilitation of the Ottoman administration, the chronic economic crisis, and arbitrary conduct of the Ottoman state authorities. The leaders of the uprising were initially successful and controlled several strategic locations and fortresses, especially in Epirus, Central Greece, and the Peloponnese. However the movement lacked the necessary organization. They were assisted by western powers; mainly by the Republic of Venice. Meanwhile the victory of the Holy League against the Ottoman fleet in the Battle of Lepanto, in November 1571, triggered further revolutionary activity. However, Venice withdrew its support to the Greek rebels and signed a unilateral peace with the Ottomans. As such the rebellion was doomed to end and the Ottoman forces committed a number of massacres in the aftermath of the revolt during the suppression of the uprising. Throughout the pacification process, various primarily isolated areas were still out of Ottoman control and new rebellions erupted, like that of Dionysios Skylosophos in 1611.