Complex sentence: The Bolsheviks, led by Vladmir Lenin came to power in October 1917, established a communist government and five months later, they signed the Treaty of Brest-Litovsk with the Germans, which formally ended the war on the Eastern Front.
Split into simpler sentences: The Bolsheviks, led by Vladmir Lenin, came to power in October 1917 and established a communist government. Five months later, they signed the Treaty of Brest-Litovsk with Germany, which formally ended the war on the Eastern Front.