Principality of Beloozero
Coordinates: 60°00′N 37°50′E / 60.000°N 37.833°E Principality of Beloozero or Beloozero Duchy (Russian: Белозерское княжество) was a Russian principality or duchy, which flourished between the 13th and 15th centuries in the Russian North. In terms of the current administrative division of Russia, the principality was located in the west of Vologda Oblast, around and south of Lake Beloye (White Lake, Russian: Белое озеро).
The principality was detached from the Principality of Rostov in 1238. The town of Beloozero (today's Belozersk) became its capital. Prince Gleb was the first prince of Beloozero (ca. 1238-1278). He increased his standing enormously by marrying Sartaq's daughter. The later rulers of Beloozero could claim a descent from Genghis Khan through this marriage. During Gleb's reign, the duchy's territory embraced the basin of White Lake, the lower streams of the Sheksna River, and Lake Kubenskoye.
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