During their independence, the Kalmyks both raided[1] and allied with Russia in turn, engaging in numerous military expeditions against the Crimean Tatars, the Ottoman Empire, neighboring Muslim tribes, and the highlanders of the North Caucasus.

Upon arrival in the lower Volga region in 1630, the Oirats encamped on land that was once part of the Astrakhan Khanate, but was then claimed by the Tsarist government.

The region was lightly populated, from south of Saratov to the Russian garrison at Astrakhan, and on both the east and the west banks of the Volga River.

Large groups of Nogais fled southeast to the northern Caucasian plain and west to the Black Sea steppe, lands claimed by the Crimean Khanate, itself a vassal or ally of Ottoman Turks.

During the era of Ayuka Khan, the Oirats rose to political and military prominence as the Tsarist government sought the increased use of Oirat cavalry in support of its military campaigns against the Muslim powers in the south, such as Persia, the Ottoman Empire, the Nogays and the Kuban Tatars and Crimean Khanate.

Ayuka Khan also waged wars against the Kazakhs, subjugated the Mangyshlak Turkmens, and made multiple expeditions against the highlanders of the North Caucasus.

The provision of monetary payments and dry goods, however, did not stop the mutual raiding, and in some instances, both sides failed to fulfil their promises.

Fred Adelman described this era as the Frontier Period, lasting from the advent of the Torghut under Kho Orluk in 1630 to the end of the great Khanate of Kho Orluk's descendant, Ayuka Khan, in 1724, a phase accompanied by little discernible acculturative change (Adelman, 1960:14–15): During the era of Ayuka Khan, the Kalmyk Khanate reached its peak of military and political power.

The Khanate experienced economic prosperity from free trade with Russian border towns, Qing China, and their Muslim neighbors.

Most likely in the 15th century, the four major West Mongolian tribes formed an alliance, adopting "Dörbet Oirat" as their collective name.

Such scholars (e.g. Sebastian Muenster) have relied on Muslim sources who traditionally used the word Kalmyk to describe the Oirats in a derogatory manner.

The policies of Saint Petersburg, for instance, encouraged the establishment of Russian and German settlements on pastures the Kalmyks used to roam and to feed their livestock.

Under Ubashi Khan's leadership, approximately 200,000 Kalmyks began the journey from their pastures on the left bank of the Volga River to Dzungaria.

Various estimates put the size of the departing group at about 169 000 humans, with perhaps as many as six million animals (cattle, sheep, horses, camels and dogs).