it necessary to move to the northeast where they found a new home in the princedoms of the upper Volga River and Oka River. As the invading Mongols ravaged the countryside, entire populations were wiped out. The peasant and serf classes were nearly destroyed en totalium; the continuation of the historical family commune social structure was broken and proved ineffective for large-scale governmental control. Most of the minor princedoms were destroyed. Most cities in the Rus' were razed and the population found it necessary to flee to the northeast in hopes of escaped the wrath of the Golden Horde. As the Golden Horde expanded across Asia, the Khanate found it necessary to incorporate different governing aspects of the peoples it conquered; from these, much was taken from the Chinese. Their philosophy on autocratic dual government was carried from the Tatar state all the way to Muscovite Rus'. The ruling Khanate injected the Mongol governing ideology into the Rus', formed its princes to this mold and exacted control on the society as dictated by their synthesized theorem of government and established dominance over the Rus' political structure. The Mongols realized the importance of cultural assimilation and local government. Mongols borrowed the political and cultural ideas from the societies they conquered. The Qipchaq idea of dual government, a principle of dual civil-military administration used to affect control over a large area, was initially developed by the Han Chinese. Han civil code, with the synthesis of Islamic iqtā, a system of decentralized cavalry control (power dispersion), proved to be an effective way of governing the Mongols' empire. After the death of Genghis Khan it was obvious the succeeding khans needed to implement effective government control over their subjects; the importance of local government, run by the natives, became evident. By the early 14th century, the Prince of Moscow was seen as one of the chief princes of the Rus', and by the late 14th century recognized as the chief prince of Rus', or Grand Prince. Consequently, the Khanate granted him the governing power of the Mongolian basqaqs, or governor. Power was laid to the prince to collect taxes and use military force to maintain order. When the Khan was thoroughly convinced the Grand Prince could perform all the duties of the basqaqs effectively, he was given total control and the Mongol basqaqs were withdrawn from the Rus'. Although the Khan removed his governors