Despite the abolition of slavery in Russia in 1723, when Peter the Great converted household slaves to serfs, Russia remains the 6th largest holder of slaves, estimated at 516,000 in 2013.
Above is based on a Global Slavery Index report that mentions unsatisfactory living conditions of migrant workers who for a number of reasons can not obtain work permits in Russia but continue to work in the country illegally and for minimum wage.
In Kievan Rus and Muscovy, legal systems usually referred to slaves as kholopy. A kholop's master had unlimited power over his life: he could kill him, sell him, or use him as payment upon a debt. The master, however, had responsibility before the law for his kholop's actions. Individuals could become kholop as a result of capture, selling themselves, being sold for debts, committing crimes, or marriage to a kholop. Until the late 10th century, the kholopy represented a majority among the servants who worked lords' lands.
The Russian lands continued in their historic function as a source of slaves for outsiders. For example, in 1382 the Golden Horde under Khan Tokhtamysh sacked Moscow, burning the city and carrying off thousands of inhabitants as slaves; similar raids occurred routinely until well into the 16th century. In 1521, the combined forces of Crimean Khan Mehmed I Giray and his Kazan allies attacked Moscow and captured thousands of slaves. In 1571, the Crimean Tatars attacked and sacked Moscow, burning everything but the Kremlin and taking thousands of captives as slaves. In Crimea, about 75% of the population consisted of slaves.Crimean–Nogai raids into East Slavic lands continued into the 18th century.
Russian slavery did not have racial restrictions. Russian girls were legally allowed to be sold in Russian controlled Novgorod to Tatars from Kazan in the 1600s by Russian law. Germans, Poles, and Lithuanians were allowed to be sold to Crimean Tatars in Moscow. In 1665 Tatars were allowed to buy from the Russians, Polish and Lithuanian slaves. Before 1649 Russians could be sold to Muslims under Russian law in Moscow. This contrasted with other places in Europe outside Russia where Muslims were not allowed to own Christians.