Russia entered World War One shortly after it started. Austria- Hungary had given Serbia an ultimatum the small country couldn't possibly accomplish. When Serbia didn't comply with the demands, Austria-Hungary declared war on Serbia. At the time, Russia believed in a principle called Pan-Slavism. This was a form of nationalism in which they believed all Slavic peoples shared a common bond through their nationality. Russia felt a need to defend the smaller country and, in turn, declared war on Austria-Hungary.
Russia was one of the allied powers in the war, along with Brittian and France. The country helped to fight against countries aligned with Austria-Hungary. Russia, however, was ill-prepared for war. They lacked the technology of superior countries, such as Germany. Russian soldiers didn't even have enough weaponry to go around. They went into the front in pairs and picked up the weapons of the dead. In total, roughly between 900,000 and 2,500,000 million soldier were killed. Some 4 million Russians were taken in as POWs. The war devastated Russia totally.
One deafining blow to Russia's morale was the Battle of Tannenberg. Russia had advanced into Germany's territory in Prussia. The German armies felt very threatended by Russia's advance. Eventually, Germany attacked the Russian army. The fighting went on for four long days. The Russian army was defeated by the mightier German army. The defeat was so horrendous the leader of the Russian Second Army, which had been heavily involved in the fight, shot himself. The German army then proceeded to drive the Russians completely out of Prussia.
Russia was also dealing with bad conditions at home. The Russian people were terribly unhappy. They were suffering from the horrible loses of the war. In the midst of the war, unfortunately, Russia also began to feel the effects of famine. Tsar Nicholas II was the ruler in charge of Russia at the time. He made the fatal mistake of appointing himself Commander-in-chief of the army.