On 20 November 1917, amid the chaos of the eastern front in WWI and the Bolshevik seizure of power in Russia, the Central Rada, which in April 1917 became the revolutionary parliament that presided over the movement for an independent Ukrainian state, declared the Ukrainian National Republic (also known as the Ukrainian People’s Republic – UNR), which maintained ties with Russia. On 22 January 1918 the Central Rada issued the Fourth Universal, which proclaimed an independent Ukrainian state. Ukrainian historian Mykhailo Hrushevsky was declared president of the new state. In the chaotic conditions, the Central Rada was unable to maintain order and a German-backed coup led by Hetman Pavlo Skoropadsky seized power. Austro-Hungary and Germany occupied much of the territory of Ukraine and supported the Hetman, who cooperated with them. His policies of grain requisition and restoration of land to wealthy landowners made his government unpopular, and in December 1918 the Directory took Kyiv and forced Skoropadsky into exile. The Directory, led by Symon Petliura, re-established the UNR. Major hostilities in Ukraine broke out again in January 1919, and the armies of the UNR had to fight the Bolsheviks and the White Army from the east, and the Poles, Germans and Romanians from the west. After signing a treaty with the new Polish state in April 1920, the UNR armies and Polish forces retook Kyiv from the Bolsheviks. A Red Army counteroffensive in the summer forced the Ukrainians and Poles into retreat, and an armistice was signed between Poland and Soviet Russia in late 1920. In the Treaty of Riga (March 1921), Poland was given the lands of Galicia and a large part of Volyn, while central, eastern and southern Ukrainian lands became part of Soviet Ukraine. Left to fight the Red Army on its own, the armies of the UNR were defeated and in 1922, Soviet Ukraine joined the Union of Soviet Socialist Republics.