Answer based on context:

As early as late 1919 the leader of Russia's new Bolshevik government, Vladimir Lenin, inspired by the Red Army's civil-war victories over White Russian anti-communist forces and their Western allies, began to see the future of the revolution with greater optimism. The Bolsheviks proclaimed the need for the dictatorship of the proletariat, and agitated for a worldwide Communist community. They had an avowed intent to link the revolution in Russia with an expected revolution in Germany and to assist other Communist movements in Western Europe; Poland was the geographical bridge that the Red Army would have to cross to provide direct physical support in the West.Lenin aimed to regain control of the territories abandoned by Russia in the Brest-Litovsk Treaty of March 1918, to infiltrate the borderlands, to set up Soviet governments there as well as in Poland, and to reach Germany - where he expected a Socialist revolution to break out. He believed that Soviet Russia could not survive without the support of a socialist Germany. By the end of the summer of 1919 the Soviets had taken over most of Ukraine, driving the Ukrainian Directorate from Kiev. In February 1919 they also set up a Lithuanian-Belorussian Republic . This government was very unpopular due to terror and the collection of food and goods for the army. Officially, however, the Soviet Government denied charges of trying to invade Europe. As Polish-Soviet fighting progressed, particularly around the time Poland's Kiev Offensive had been repelled in June 1920, the Soviet policy-makers, including Lenin, increasingly saw the war as a real opportunity to spread the revolution westwards. Historian Richard Pipes noted that before the Kiev Offensive, the Soviets had prepared for their own strike against Poland.

What happened second, Brest-Litovsk Treaty or set up a Lithuanian-Belorussian Republic?
Lithuanian-Belorussian Republic