Free tenants on the lands of the nobles, individual freeholders (_odnodwortsy_), etc., and the numerous rural communities owning land unconditionally and paying therefrom tribute--rather as public taxation--to the ducal treasury, constituted the rural population of Russia. From the time of Yaroslaw to the end of the sixteenth century, not one-tenth of the population was in the condition of _rab_, _krepostnoi kholop_, or serfs by writ or _kabala_. The almost boundless extent of land constituting Russia was as yet unsurveyed, and no regular limits divided or marked the landed property. Thus it was easy for the strong to encroach on the lands of the rural communes, or on the new clearings made by individual freemen; and such annexations were often practised during the domestic wars between the numerous dukes, and during the time of Tartar domination. Iwan the Great (1462-1503) ordered, that whoever held a piece of land in undisputed possession for three years became its legal owner. But even the encroachments of the nobles did not transform the free laborers or tenants into serfs; and when a landlord was oppressive, whole villages abandoned him and contracted for land on other estates. Chattels (_rab_, _krepostnoi kholop_) might be emancipated by the free will of the master; and a captive carried away by the Tartars, or a prisoner of war if a _kholop_, became free if he succeeded in escaping from captivity and returning to his country. In the sixteenth century, all classes of the rural population began to be called Christians (_krestianin_), the Tartars having bestowed this denomination on them; and this name is now legally in use. Under Tartar dominion the rural communities paid tribute per head; and for this reason their members could not change their domicile without giving security to the commune. But after the overthrow of the Tartars by Iwan the Great, they recovered the freedom of circulation. The primitive grand-dukes of Kief granted appanages to their younger children, and sometimes a free rural commune constituted such an appanage. Vladimir, and after him Yaroslaw, divided the empire among their children; and thus originated the rather independent dukedoms of Twer, Smolensk, Wiazma, etc. The number of appanaged princes increased; and when, after a long and bloody struggle, the grand-dukes of Moscow _mediatized_ all these small dukes, appanages became private property, and the rural communes were owned by the dukes (_kniazia_), but under similar conditions of freedom as the communes constituting the public domains.