ABSTRACT
Restricted in their spread to west and south, the great expansion of the Russians moved north and east into vast expanses of terraincognita, where they contributed to geographical knowledge by their explorations. Long before any Russian state appeared, the Slavs lived in the marshy valleys of the middle Vistula, the Pripyat, and the upper Dnepr. Nomad decline allowed the Russians to push their boundaries in the eighteenth and nineteenth centuries to the Black Sea littoral and deep into Central Asia, until they impinged on the national or imperial interests of other powers. In the unsuccessful struggle with the Germans, Letts and Lithuanians moved eastwards into the thinly-settled marchlands of Russia. The Mongol invasion became one of the most significant formative periods in Russian nationhood. The central position of Moscow placed it well to expand and unite other Russian principalities.
