Initially, following the October Revolution in 1917, the USSR was made up of a confederation of Russia, Belarus, Ukraine, and the Transcaucasian Federation (modern-day Georgia, Armenia and Azerbaijan). The USSR developed to include 15 republics, they were: Russia, Georgia, Armenia, Azerbaijan, Belarus, Ukraine, Moldova, Turkmenistan, Latvia, Estonia, Lithuania, Kazakhstan, Tajikistan, Uzbekistan, and Kyrgyzstan.