What happened
Over six decades Russia absorbs the region — Georgia annexed from 1801, the Persian khanates including Karabakh, Erivan and Nakhchivan ceded by the treaties of Gulistan (1813) and Turkmenchay (1828), and the mountain North Caucasus subdued only after the long Caucasian War against Imam Shamil, ending in 1859 in Chechnya and Dagestan and in 1864 in the west with the expulsion of most of the Circassian population to the Ottoman Empire.
The conquest set the region's demographic and administrative baseline — which communities lived where, under what borders — and gave the North Caucasus a memory of subjugation by force that both Chechen wars would consciously invoke.
Confidence: High
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