Ukraine first proclaimed its independence in 1917 and attempted to fight a war against Soviet Russia. By 1920, it had lost the war and was incorporated into the Soviet Union in 1922.
The Ukrainian civil war was especially brutal and with heavy civilian casualties. In 1921-22, over 10,000 members of the Ukrainian army were shot by Soviet authorities. To level Ukraine and eliminate resistance, the communist regime artificially induced the mass famines of 1921-23, 1932-33 and 1946-47 in which up to 13 million people perished. The notorious 1932-33 famine was used to carry out forced collectivization.
The Ukrainian culture and language fell under heavy pressure and a russification campaign was launched. Another wave of terror struck Ukraine after WWII, this time targeting alleged collaborators. The communist regime resorted to ruthless measures, including civilian mass deportations, to put down an armed anti-Soviet rebellion in Western Ukraine. Meanwhile, Ukrainian Catholic Church was declared lawless.
The number of victims of communism in Ukraine has been estimated at 15 million. This does not include Ukrainian deaths in WWII, which the Soviets helped trigger by cooperating with Nazi Germany. Although Ukraine has been independent since 1991, the decades of Soviet dependency are hard to overcome.