|Belarus Table of Contents
Belarus's origins can be traced from the emergence in the late ninth century A.D. of Kievan Rus', the first East Slavic state. After the death of its ruler, Prince Yaroslav the Wise, in 1054, Kievan Rus' split into a number of principalities, each centered on a city. One, Polatsk (Polotsk, in Russian), became the nucleus of modern-day Belarus.
In 1240, after the Tatar overthrow of Kiev, the dominant principality of Kievan Rus', Belorussia and part of Ukraine came under the control of Lithuania. The resulting state was called the Grand Duchy of Lithuania, Rus', and Samogitia. Because territories inhabited by East Slavs made up about 90 percent of the Grand Duchy, they exerted a great cultural influence on the new state. Official business was conducted in a Slavic language (a predecessor of both Belorussian and Ukrainian) based on Old Church Slavonic, and the law code was based on that of Kievan Rus'.
Source: U.S. Library of Congress