contested between the Qara Qoyunlu and their rivals, the Timurid-allied Aq Qoyunlu. In 1451 the Qara Qoyunlu besieged the city after it had been captured by the Aq Qoyunlu, but failed to retake the stronghold. Aq Qoyunlu rule thus continued in the city for the rest of the 15th century. Coins were struck here under the rule of Uzun Hasan and his son, Ya'qub. After Ya'qub, Aq Qoyunlu rule began to fragment, but Mardin remained the center of an independent Aq Qoyunlu principality for many years, while the Safavids in the east grew stronger. In 1507, the Safavid ruler Ismail I succeeded in capturing the city and the castle, expelling the local Aq Qoyunlu ruler. During the medieval period, the town retained significant Assyrian and Armenian populations and became the centre for episcopal sees of Armenian Apostolic, Armenian Catholic, Church of the East, Syriac Catholic, churches, as well as a stronghold of the Syriac Orthodox Church, whose patriarchal see was headquartered in the nearby Saffron Monastery from 1034 to 1924. A Venetian merchant who visited the town in 1507 wrote that there were still more Christian Armenians and Jews in the city than Muslims. Ottoman Empire After the Ottoman victory against their bitter rivals, the Safavids, at the Battle of Chaldiran in 1514, the balance of power in the region changed. The Safavid commander in the region, Ustajlu, was killed in the battle with the Ottomans and was replaced by his brother, Kara Khan (or Karahan). In 1515 Mardin briefly yielded to the Ottomans, but the castle remained under Safavid control and the Ottomans were forced to leave after a few days, leaving Kara Khan to re-occupy it. The following year, the Ottoman commander, Bıyıklı Mehmed Pasha, defeated Kara Khan and Safavid control in the region crumbled. The Ottomans besieged Mardin again, which resisted under the command of Kara Khan's brother, Sulayman Khan. After the Battle of Marj Dabiq in August 1516, Bıyıklı Mehmed Pasha returned with reinforcements from Syria and finally forced the city's surrender in late 1516 or early 1517. After this, Mardin was administered by a governor directly appointed under the Ottoman Sultan's authority. The city experienced a relatively tranquil period under Ottoman rule, without any significant conflicts or plights. European travelers who visited the city in the late 18th and early 19th centuries gave highly variable estimates of the population, but generally indicate that Muslims (or