To discuss this question fully it would be necessary to enter into certain debated points of mediaeval history.  All I can do here is to indicate what seems to me the true explanation.

In Central Europe, all through the Middle Ages, a perpetual struggle went on between the various political factors of which society was composed, and the important towns were in a certain sense the products of this struggle.  They were preserved and fostered by the mutual rivalry of the Sovereign, the Feudal Nobility, and the Church; and those who desired to live by trade or industry settled in them in order to enjoy the protection and immunities which they afforded.  In Russia there was never any political struggle of this kind.  As soon as the Grand Princes of Moscow, in the sixteenth century, threw off the yoke of the Tartars, and made themselves Tsars of all Russia, their power was irresistible and uncontested.  Complete masters of the situation, they organised the country as they thought fit.  At first their policy was favourable to the development of the towns.  Perceiving that the mercantile and industrial classes might be made a rich source of revenue, they separated them from the peasantry, gave them the exclusive right of trading, prevented the other classes from competing with them, and freed them from the authority of the landed proprietors.  Had they carried out this policy in a cautious, rational way, they might have created a rich burgher class; but they acted with true Oriental short-sightedness, and defeated their own purpose by imposing inordinately heavy taxes, and treating the urban population as their serfs.  The richer merchants were forced to serve as custom-house officers—­often at a great distance from their domiciles*—­and artisans were yearly summoned to Moscow to do work for the Tsars without remuneration.

     * Merchants from Yaroslavl, for instance, were sent to
     Astrakhan to collect the custom-dues.

Besides this, the system of taxation was radically defective, and the members of the local administration, who received no pay and were practically free from control, were merciless in their exactions.  In a word, the Tsars used their power so stupidly and so recklessly that the industrial and trading population, instead of fleeing to the towns to secure protection, fled from them to escape oppression.  At length this emigration from the towns assumed such dimensions that it was found necessary to prevent it by administrative and legislative measures; and the urban population was legally fixed in the towns as the rural population was fixed to the soil.  Those who fled were brought back as runaways, and those who attempted flight a second time were ordered to be flogged and transported to Siberia.*

     * See the “Ulozhenie” (i.e. the laws of Alexis, father of
     Peter the Great), chap. xix. 13.