Crimea should be considered part of Ukraine.
Prior to being incorporated into the Russian Empire, the Crimean Peninsula was independent under the Crimean Khanate.
In 1774, following the Russo-Turkish War of 1768–74, the Russian and Ottoman empires agreed to refrain from interfering with Crimean Khanate through the Treaty of Küçük Kaynarca.
In 1783, the Russian Empire annexed the Crimean Khanate.
In 1944 Lavrentiy Beria, head of the Soviet state security and secret police ordered the forced deportation of the Crimean Tatars from the Crimean peninsula on behalf of Joseph Stalin, resulting in the ethnic cleansing of the region. As a result, this region was now predominantly ethnically Russian.
In 1954, Nikita Khrushchev transferred the Crimean Oblast from the Russian SFSR to the Ukrainian SSR.
In 1992 Ukraine, including Crimea, became independent again.
In 2014 Russia annexed Crimea again.
This was the beginning of the Russian invasion of Ukraine that expanded further in 2022.
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