 Thus, in September 1656 Valide Sultan Turhan Hatice selected Köprülü Mehmed Pasha as grand vizier, as well as guaranteeing him absolute security of office.She hoped that a political alliance between the two of them could restore the fortunes of the Ottoman state.Köprülü was ultimately successful; his reforms enabled the empire to break the Venetian blockade and to restore authority to the rebellious Transylvania.