Which of the following explains why people use 1918 as the state date of the Russian Civil War

One possible explanation for why people use 1918 as the start date of the Russian Civil War is that it marks the beginning of widespread armed conflict between different factions in Russia. In March 1918, the Bolshevik government signed the Treaty of Brest-Litovsk, which ended Russia's involvement in World War I and ceded large territories to Germany and its allies. This treaty sparked opposition and dissent from various groups across the country, including anti-Bolshevik forces known as the White Army, who saw the Bolsheviks as traitorous and sought to overthrow them.

Furthermore, in July 1918, the execution of Tsar Nicholas II and his family in Ekaterinburg further heightened tensions and division within Russia. This event galvanized anti-Bolshevik sentiment and increased support for the White Army. Thus, 1918 is seen as the starting point of the Russian Civil War due to these significant events and the subsequent escalation of violence and conflict between the Bolsheviks and their opponents.