Truvor and Sineus according to the 12th-century Primary Chronicle

Primary Chronicle

The Primary Chronicle , Ruthenian Primary Chronicle or Russian Primary Chronicle, is a history of Kievan Rus' from about 850 to 1110, originally compiled in Kiev about 1113.- Three editions :...

 were the brothers of Rurik

Rurik

Rurik, or Riurik , was a semilegendary 9th-century Varangian who founded the Rurik dynasty which ruled Kievan Rus and later some of its successor states, most notably the Tsardom of Russia, until 1598....

 of the Varangian  Rus tribe.

While Rurik settled in Novgorod, Sineous established himself at Belo Ozero

Belozersk

Belozersk , known as Beloozero until 1777 , is a town and the administrative center of Belozersky District of Vologda Oblast, Russia, situated on the southern bank of Lake Beloye, from which it takes the name...

, on the shores of lake Beloye. Truvor established himself at Izborsk

Izborsk

Izborsk is a rural locality in Pechorsky District of Pskov Oblast, Russia. It contains one of the most ancient and impressive fortresses of Western Russia....

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Truvor and Sineus died shortly after the establishment of their territories. Rurik then consolidated these lands into his own territory and thus laid the foundations for the Kievan Rus'

Kievan Rus'

Kievan Rus was a medieval polity in Eastern Europe, from the late 9th to the mid 13th century, when it disintegrated under the pressure of the Mongol invasion of 1237–1240....

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