Crimean-Nogai raids into East Slavic lands

The Crimean-Nogai raids were slave raids by the Khanate of Crimea and the Nogai Horde into the region of Rus' then controlled earlier by the Grand Duchy of Moscow and later Tsardom of Russia and the Grand Duchy of Lithuania (later part of the Polish–Lithuanian Commonwealth). They began after Crimea became independent about 1441 and lasted until Crimea was brought under Russian control in 1774. Their main purpose was the capture of slaves, most of whom were exported to the Ottoman slave markets in Constantinople or elsewhere in the Middle East. The raids were an important drain of the human and economic resources of both countries. They largely prevented the settlement of the "Wild Fields" – the steppe and forest-steppe land that extends from a hundred or so miles south of Moscow to the Black Sea and now contains most of the Russian and Ukrainian population. The raids were also important in the development of the Cossacks.

The number of people involved varies: according to Alan W. Fisher the number of people deported from the Slavic lands on both sides of the border during the 14th to 17th centuries was about 3 million people. Michael Khodarkhovsky estimates that 150,000–200,000 people were abducted from Russia in the first 50 years of the 17th century. By way of comparison, the Atlantic Slave Trade affected about 12 million people, while Arabs captured 10 to 18 million African slaves over a much longer period.

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