The First World War broke out in 1914 between the Entente powers comprising Russia, France, UK, Canada, Australia, Italy, Japan and America and the Central powers comprising Germany, Austria, Hungary, the Ottoman Empire and the kingdom of Bulgaria.
Led by Tsar Nicholas II, Russia got pulled into the First World War and Tsar started taking decisions without consulting the Duma. Russia had the largest army but they suffered heavy causalities during the battle to Germany and Austria.
While retreating they destroyed crops and buildings leaving lots of people homeless. The war had a severe impact on the industry and Germany cut the supplies coming to Russia through the Baltic Sea.
Labour shortages followed which led to the shutting down of workshops. Large supplies of grain were being sent to feed the army, leaving very little for the people back home. By the winter of 1916, fighting and riots started breaking out at bread shops. The Tsar and the royal family hence became very unpopular.