From the end of the sixteenth century until 1861, vast numbers of Russian peasants were classed as serfs - in other words, slaves tied to the land, who could be bought, sold or gambled away as part of the estates of their landowners. By the beginning of the nineteenth century an estimated 50% of Russian peasants were serfs; the system underpinned Russia's stagnant agricultural economy. Although they were most often bought and sold along with the land to which they were bonded, skilled serfs could also be sold individually, as here with Taras. For centuries, periodic peasant-led rebellions broke out against the system, the most famous of which being those led by Stenka Razin (1667-71) and Yemelyan Pugachev (1773–1775). Despite this, the system persisted, held in place by powerful, aristocratic landowners and indifferent or reactionary tsars. It was finally abolished by Alexander II (grandson of Alexander I) by means of the Emancipation Act of 1861.
In a burst of liberal enthusiasm in 1856 Tolstoy began talks with his own serfs, offering to free them and give them land in exchange for compensation. However Tolstoy's peasants believed they would soon be granted unconditional land and freedom, so they refused to go along with his ideas. Tolstoy was troubled that landowners such as himself would not be properly compensated if the serfs were emancipated, and irritated by his own serfs' suspicious attitudes. The ambiguity in his portrayal of serfs - partly as the only authentic Russians, partly as backward and close-minded - reflects this incident.
The issue of serfdom appears in many works by nineteenth century Russian writers, most famously in Nikolai Vasilievich Gogol's Dead Souls. Tolstoy's most interesting treatment of this subject is arguably his 1895 story Master and Man, which can be read online here.
Unfortunately slave labour still exists in Russia today, as it does in many other parts of the world, including England. In February 2009 Human Rights Watch issued a report on the abuses of migrant workers in Russia, many of whom are tricked by 'employment agencies' who confiscate their passports and force them into unpaid manual labour or prostitution.