Mansur Beg was a Safavid official, who served as the first Safavid governor (hakem) of Derbent (Darband), in 1509, during the reign of king Ismail I (r. 1501-1524). Following his brief tenure, he was succeeded by members of the Shirvanshah family who governed the city under Safavid suzerainty until 1538. After that, directly appointed Safavid governors came to govern it again.
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Mansur Beg (governor of Derbent) Wikipedia(Text) CC BY-SA