THE fundamental fact of Russian history is the colonisation of the Great Russian Plain by people who are not known to have been indigenous in any part of the region. The Eastern Slavs, who formed the nuclear group of these people, had an origin which is now obscure; but they appear to have entered upon the Russian Plain from "one of its corners," from the Carpathian Mountains on the south-west. In his brilliant account of the course of Russian history1 Professor Kluchevsky divides this history into four periods: First, from the eighth till the thirteenth century; Second, from the thirteenth till the middle of the fifteenth century; Third, from the middle of the fifteenth till the second decade of the seventeenth century; and Fourth, from the latter date until the middle of the nineteenth century.
To these four periods we may add a Fifth, from the middle of the nineteenth century up till the close of the Russian Revolution in 1905-1906.
The First period was characterized by the political division of the land under the leadership of the trading towns. The Second period was characterized by the agricultural exploitation of the heavy clay soil of the Moscow region, by means of free peasant labour under the princes of the Udeli of the Upper Volga. The Third period was characterized by the political union of the principalities into the Russian State, the chief economic fact being the working of the heavy soils of the Upper Volga and of the Don Black Soil region, still by free peasant labour. But the freedom____________________