The Calmucks are a branch of the Mogul or Mongol nation, which originally inhabited the country to the north of China. In the latter part of the seventeenth century, the Torgot and Derbet divisions of this tribe descended to the banks of the Volga, extending their wanderings over the country of the Don Cossacks to the shores of the sea of Azov. About this time Ayuka Khan ruled over the whole nation. Shortly after his death, and while weakened by internal dissensions, the Calmucks fell an easy prey to the designs of the Russian government, and remained subject to the imperial sceptre, until, in the winter of 1770-1771, offended by the despotic measures of the empress Catherine II., half a million of the tribe wandered rather farther than usual, and ended by pitching their tents in the dominions of " his celestial majesty" the emperor of China—a warning to despotic governments not to trouble their nomadic subjects with the arrangements of the " home department."
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Sears, Robert. An Illustrated Description of the Russian Empire. New York: Robert Sears, 1855