Truvor and Sineus according to the 12th-century Primary Chronicle were the brothers of Rurik of the Varangian Rus tribe. The two names are believed to be a Slavic misunderstanding based on the Scandinavian expressions Trú vor ("our faithful") and Sine hus ("his households" or "his clan").
According to the Primary Chronicle, while Rurik settled in Novgorod, Sineous established himself at Belo Ozero, on the shores of lake Beloye. Truvor established himself at Izborsk. 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'.
The current scholarly interpretation is that "Rurik, Sineus, en Truvor" should be read "Rurik, sine hus, en tro(gna) vär(ingar)" (Rurik, his house/relatives, and true companions). [1]