Zahir al-Umar al-Zaydani, alternatively spelled Daher al-Omar or Dahir al-Umar (Arabic: ظاهر العمر الزيداني, romanized: Ẓāhir al-ʿUmar az-Zaydānī, 1689/90 – 21 or 22 August 1775) was the autonomous Arab ruler of northern Palestine in the mid-18th century, while the region was part of the Ottoman Empire. For much of his reign, starting in the 1730s, his domain mainly consisted of the Galilee, with successive headquarters in Tiberias, Deir Hanna and finally Acre, in 1750. He fortified Acre, and the city became the center of the cotton trade between Palestine and Europe. In the mid-1760s, he reestablished the port town of Haifa nearby.