The history of Ukrainian Republic as Ukrainian Soviet Republic and its government begins from 24–25 December 1917 when in Kharkiv the First All-Ukrainian Congress of Councils (radas, soviets) was conducted, which declared Ukraine as Ukrainian Republic, Ukrainian People's Republic of Soviets – Ukrainian Soviet Republic. Congress made a decision to get a close alliance with Russian Republic (also Soviet) and elected Central Executive Committee (Ukrainian: ЦВК).
Military forces of Soviet government of Ukrainian Republic of that time are known as Red Cossacks Army, later integral part of Red Army of the Soviet Union.
On April 18, 1918, in Taganrog,[1] the next session of the Central Executive Committee of Soviets announced that the government of Soviet Ukraine, the Central Executive Committee of Ukraine and the People's Secretariat were now combined as the "Ukrainian Bureau" to guide the insurgent struggle against the German occupation.