In the mid-18th century, Zahir al-Umar, the autonomous Arab ruler of the Galilee became a dominant figure in Palestine. To build up his army, he strove to gain a monopoly over the cotton and olive oil trade of the southern Levant, including Jabal Nablus, which was a major producer of both crops. In 1771, during the Egyptian Mamluk invasion of Syria, Zahir aligned himself with the Mamluks and besieged Nablus, but did not succeed in taking the city. In 1773, he tried again without success. Nevertheless, from a political perspective, the sieges led to a decline in the importance of the city in favor of Acre. Zahir's successor, Jezzar Pasha, maintained Acre's dominance over Nablus. After his reign ended in 1804, Nablus regained its autonomy, and the Tuqans, who represented a principal opposing force, rose to power.