1914 - August/September: August 17th the Russian Army moved into East Prussia. General Alexander Samsonov advanced slowly into the south-west corner. The intention of this attack was to link up with the other major Russian army coming from the north-east (under General Paul von Rennenkampf).
Battle of Tannenberg and Battle of the Masurian Lakes: August 20th 1914 – the Russian General von Rennenkampf defeated a German force at Gumbinnen. Paul von Hindenburg and Erich von Ludendorff realized the threat and decided to move a few divisions from the Western front to the Eastern front (around 100,000 men – this ruined the Schlieffen Plan). They made contact with the Russian troops August 22nd 1914 . The two Russian armies were separated by 80 km. This made it possible for Hindenburg and Ludendorff to tackle them individually. Samsonovs troops were surrounded and defeated outside Tannenberg (“Battle of Tannenberg” August 26th-29th 1914 ) and Rennenkampf’s Army was defeated two weeks later at the “Battle of the Masurian Lakes”. Out of 150,000 Russian soldiers only around 10,000 managed to escape. General Samsonov committed suicide!

1914 September - 1915 August: Russian troops invaded Galicia. Lvov (Lemburg) was captured by Russian troops in September 1914. This revealed the fact that the Austrian-Hungarian army was poorly organized. The Russian army fought well but they also had some problems which would make a difference in the long run; poor and split leadership, not enough equipment and they were underfed! The Austrian-Hungarian armies were forced to retreat to the Carpathian Mountains. Then German re-enforcements under General Ludendorff arrived. The German soldiers were in general better equipped, well supplied, better trained and they were often transported by trains between the different battle zones which made them arrive fairly rested. During the German Austrian-Hungarian campaign in the Carpathian Mountains (May 1915) and the German campaign through Poland (Warsaw captured August 1915) the Russian forces were forced to retreat. By the end of 1915 the Russian lines had withdrawn some 450 km.

Results: RUSSIAN INITIAL VICTORY against Austria-Hungary . GERMAN VICTORY through two campaigns in 1915; Campaign in the Carpathian Mountains and the Campaign through Poland.

1916: Early in 1916 France called upon Russia to help relieve the pressure on Verdun by launching an offensive against the Germans on the Eastern Front, hoping Germany would transfer more units to the East to cope with the Russian attack. The Russians responded by initiating the disastrous Lake Naroch Offensive in the Vilno area, during which the Germans suffered just 1/5 as many casualties as the Russians.

In the summer of 1916, the British Somme Offensive designed to the same end had resulted in a quagmire, and the western Allies called upon the Russians again to help relieve German pressure on their front. In response, General Aleksei Brusilov presented his plan to Stavka, the Russian high command, proposing a massive offensive by his Southwestern Front against the Austro-Hungarian forces in Galicia. The main purpose of Brusilov's operation was to take some of the pressure off French and British armies in France and the Italian Army along the Isonzo Front, and if possible, to knock Austria-Hungary out of the War.

1916 June/September - the Brusilov Campaign: Three of General Brusilovs four armies reached an immediate success – within less than a week Russia had broken through the lines and taken over 70 000 prisoners. He used a new tactic - "Shock troops" were sent through the weak parts of the Austro-Hungarian lines and then the main army used the roads cleared by these troops. This is a forerunner to the Blitzkrieg Germany used in WWII. It was only in the northern sector of the Russian front where the army under General Evert stood still (General Alexei Evert, commander of the Russian Western Army Group, favored a defensive strategy and was opposed to Brusilov's offensive).

Encouraged by the positive Russian results Romania decided to join the war on the Entente side. By early August the offensive came to a halt. The Romanian forces were now in trouble and the defensive tactics of General Evert had resulted in an unsuccessful half-hearted offensive in the north. Russia now lacked resources; both reserve soldiers and supplies. At headquarters different groups of militaries tried to change the original plan which led to confusion and weakened the offensive and then Austria-Hungary received more German support. Against the will of General Brusilov troops were moved from the northern sector (General Evert) to reinforce the campaign in Galicia . This together with the Romanian army problems (General Brusilov had to send some of his army to help the Romanian army that were being overrun by German and Austro-Hungarian troops) were the main factors behind the halt of the offensive.

Results: RUSSIAN VICTORIES. The Western front as well as the Italian front was relieved. Russian troops gained territory in Galicia . The Austrian-Hungarian poor performance had a very negative effect on its fighting forces. Russia had been very close to defeat Austria-Hungary – it was only with German assistance the Dual Monarchy stayed in the war. By the end of 1916 German troops started an offensive which resulted in Russian retreat.

Russian casualties and economic hardship leads to revolution; The enormous losses in human life’s as well as the strained Russian economy brought Russia into a collapse in February 1917. What first looked like a normal strike turned into a revolution and within a few weeks the Tsar abdicated. The Romanov dynasty came to an end after over 300 years of rule! The new Provisional Government continued the war. The period between February and October 1917 saw several Russian defeats. The most serious one hit the country in June 1917 (Galician offensive or the Kerensky offensive). In October 1917 Lenin and the Bolsheviks made a second revolution. They had promised to end the war. Germany granted Russia an armistice but after waiting nearly two months for some kind of agreements Germany continued the war. Russia gave up after just a few weeks and another armistice was granted.