Final answer:
The revolutionaries succeeded in overthrowing the government in Russia during World War 1.
Step-by-step explanation:
The nation in which the revolutionaries succeeded in overthrowing the government during World War 1 was Russia.
The Russian Revolution, specifically the October Revolution of 1917, led to the Bolsheviks seizing power and establishing a communist government under the leadership of Lenin. This revolution was successful in overthrowing the existing government and creating a new social and political order in Russia.