Armenia

After the Russian Revolution of 1917 and the takeover of the Bolsheviks, S. Shaumyan was placed in charge of Armenia. In September 1917 the convention in Tiflis elected the Armenian National Council.
The signing of the Ottoman-Russian friendship (January 1, 1918), proved disastrous for the Armenians. The treaty alowed the Turks to attack the new Republic. The Democratic Republic of Armenia (DRA) was established in Erevan on May 28, 1918. Due to constant border skirmishes with Turks the Armenian government declared war on Turkey thus precipitating the Turkish-Armenian War.
The consequences of the war with Turkey were severe. In the Treaty of Alexandropol, the young Armenian republic was to disarm most of its military forces, cede more than 50% of its pre-war territory, and to give up all the territories granted to it at the Treaty of Sèvres. However, as the terms of defeat were being negotiated, Bolsheviks invaded the DRA from Azerbaijan in order to establish a new pro-Bolshevik government in the country. On November 29, the Soviet 11th Army invaded Armenia and marched into Erevan on December 4 1920.
Although the Bolsheviks succeeded in ousting the Turks from their positions in Armenia, they decided to establish peace with Turkey. In 1921, the Bolsheviks and the Turks signed the Treaty of Kars, in which Turkey ceded Adjara to the USSR in exchange for the Kars territory. The land given to Turkey included the ancient city of Ani and Mount Ararat, the spiritual Armenian homeland.
In 1922, Armenia became part of the Soviet Union as one of three republics comprising the Transcaucasian SFSR. The Transcaucasian SFSR was dissolved in 1936 and as a result Armenia became a constituent republic of the Soviet Union as the Armenian Soviet Socialist Republic.

 

Azerbaijan

At the collapse of the Russian Empire in 1917, an independent republic was proclaimed in Ganja on May 28, 1918 following an abortive attempt to establish a federal Transcaucasian Republic with Armenia and Georgia. Soon after, the Turks defeated united Azerbaijan-British forces and occupied the country causing much of the Armenian population to flee. The Ottoman Empire, however, capitulated on November 30, 1918 and the British occupational force re-entered the capital of Azerbaijan, Baku.
Azerbaijan was proclaimed a secular republic and its first parliament opened on December 5, 1918. British forces left in August, 1919. However by early 1920, advancing Bolshevik forces, victorious in Russian Civil War, started to pose a great threat to young republic which also engaged in a conflict with Armenia over the Karabakh enclave.
Azerbaijan received de facto recognition by the Allies as an independent nation in January 1920 at the Versailles Paris Peace Conference. The president of the parliament, Alimardan Topchubashev, was recognized as the head of state. In this capacity he represented Azerbaijan at the Versailles Paris Peace Conference in 1919.
The Red Army invaded Azerbaijan on April 28, 1920. It met with almost no resistance since the bulk of the newly formed Azerbaijani army was engaged in putting down an Armenian revolt that had just broken out in Karabakh. The same day a Soviet government was formed. After the surrender of the pro-British national government to Communist forces, Azerbaijan was proclaimed a Soviet Socialist Republic. It was incorporated into the Transcaucasian Soviet Federated Socialist Republic along with Armenia and Georgia in March 1922.

 

 

Georgia

The Russian Revolution of October 1917 plunged Russia into a bloody civil war during which several outlying Russian territories declared independence and Georgia was one of them. In May 1918, following the withdrawal of German forces that had occupied the area during World War I, Georgia proclaimed the establishment of the independent Democratic Republic of Georgia. The new country was ruled by the Menshevik faction of the Social Democratic Party, which established a multi-party system in sharp contrast with the "dictatorship of the proletariat" established by the Bolsheviks in Russia. It was recognized as independent by the major European powers in 1918 and by Soviet Russia in May 1920.
In February, 1921 the Red Army invaded Georgia and after a short war occupied the country. Georgian government was forced to flee. The Georgian Soviet Republic was merged into the Transcaucasian Federation of Soviet Republics in March 1922, and issues of the federation replaced those of Georgia in October 1923.

 

 

Ukraine

When World War I and the Bolshevik revolution in Russia shattered the Austrian and Russian empires, Ukrainians were caught in the middle. Between 1917 and 1918, several separate Ukrainian republics manifested independence, the Central Rada, the Hetmanate, the Directorate, the Ukrainian People's Republic and the West Ukrainian People's Republic. However, with the defeat in the Polish-Ukrainian War and after the Peace of Riga in March 1921 which ended the Polish-Soviet War, the western part of Ukraine had been incorporated into Poland, and the larger, central and eastern part became part of the Soviet Union as the Ukrainian SSR.