Hajji 'Umar, the emir of Chalybia, was neutralized by diplomacy, and he was married to Alexios' sister Theodora in 1358. Alexios continued this policy of seeking diplomatic alliances with the neighboring Muslim princes, with the marriages of four of his daughters; the fifth, Anna Megale Komnene, became the second wife of King Bagrat V of Georgia. Alexios was also unable to displace the Genoese and Venetians from their dominant position in Trebizond's commerce. The position of Venice had declined following the concession of Leonkastron to the Genoese in 1349, and in 1360 Alexios attempted to restore commercial relations with Venice to offset the power of the Genoese. In 1364 he confirmed to the Venetians their old privileges and assigned them a depot "below the monastery of the holy martyr, Theodore Gabras". But the Venetians were not content with their gains and jealously quarreled with the Genoese. Another concession to Venice followed in 1367, and gradually lowered some of the dues levied on Venetian commerce. Nevertheless, Alexios' attempt to exploit the commerce of the Italian republics resulted in considerable resentment. In 1373 the Venetians conspired with the despotes Dobrotitsa of Dobruja (an enemy of the Genoese) to impose his son-in-law Michael Palaiologos, a younger son of Emperor John V Palaiologos, upon the throne of Trebizond. Michael Palaiologos appeared before Trebizond with two large ships and a small one, and remained there for five days until he abandoned the plan and left. Relations with Venice were patched up, but although Alexios further reduced the dues he collected from the Venetians in 1381, their trade with Trebizond continued to decline. Alexios III died on March 20, 1390, and was succeeded by his son Manuel III. During his long reign, Alexios III had repaired the physical damage to the capital, gave rich endowments to several monasteries, especially Soumela Monastery, and founded the Dionysiou monastery at Mount Athos. Anthony Bryer explains this largesse was due to a series of confiscations following the defeat of the notables who had opposed a strong central government, setting forth a timeline showing how as archontes were executed and their properties reverted to the crown, he could refound monasteries such as St. Phokas in Kordyle (1362), Soumela (1364), Dionysiou (1374), and Theoskepastos (1376). "This sequence of recovery, or expansion, of the imperial demesne, which is the clue to Alexios III's triumph over his landowning rivals, is clear enough." Issue By