Annexation of Crimea by the Russian Federation military intervention in Ukraine "until normalization of a socio-political environment in the country". Putin's swift manoeuvre prompted protests of intelligentsia and demonstrations in Moscow against a Russian military campaign in Crimea. By 2 March, Russian troops moving from the country's naval base in Sevastopol and reinforced by troops, armour, and helicopters from mainland Russia exercised complete control over the Crimean Peninsula. Russian troops operated in Crimea without insignia. On 4 March Ukrainian General Staff claimed there are units of 18th Motor Rifle Brigade, 31st Air Assault Brigade and 22nd Spetsnaz Brigade deployed and operating in Crimea instead of Russian Black
Crimea by "the commonality of the economy, the proximity, and close economic and cultural relations between the Crimean region and the Ukrainian SSR". At that time no vote or referendum took place, and Crimean population had no say in the transfer (also typical of other Soviet border changes). After the annexation of Crimea by the Russian Federation, doubts have been expressed - from the Russian side by all means, but even by Western historians (Richard Sakwa, "Frontline Ukraine. Crisis In the Borderlands", 2015) - about the very legitimacy of the 1954 transition of Crimea to Ukraine; in the critics' view the