In the summer of 1914 the Austro-Serbian conflict escalated into open war. Serbia has traditionally relied on the support of Russia. As part of the Russian military districts, on the Black Sea and Baltic fleets conducted mobilization, which grew in total. In response, Germany August 1, 1914 also launched a mobilization campaign, and in the evening the German ambassador in St. Petersburg presented Russian Foreign Minister note declaring war on Russia. On August 3 note of the same content delivered to the French government. Accusing the French of violating the neutrality of Belgium, Germany, without warning invaded its territory. This led to war England.

Within days the war broke out across the globe. On the side of the Entente was Japan, with a view to capture German colonies in the Pacific and inherit China. In Germany also joined the Ottoman Empire. Formed new fronts in the Caucasus, Syria, Palestine. But from the beginning were the main western and eastern fronts in Europe. In the West German forces opposing the British, French and Belgian armies. In the east, the combined forces of the German and Austro-Hungarian armies were directed against Russia.

Early in the war unprecedented patriotic and nationalistic exaltation seized public warring states. Outward expression of national sentiments were renaming of towns with German names, including St. Petersburg became Petrograd; in the British royal family, who was born in Hanover, Germany, has a new name - Windsor.

On the eve of the war the Entente had the advantage of human and material resources of the countries of the Triple Alliance. Navies of Britain and France dominated the seas. But the quantity and quality of arms and in terms of mobilization for war better prepared Germany. Almost a year before the outbreak of hostilities in Germany was prepared military and operational plan to attack France. The basis of these hostilities was the Schlieffen Plan General - Chief of Staff of the German in the 1891-1905 biennium.

The inevitability of war on two fronts Germany was evident. So the main idea of ​​the strategic plan was to beat opponents apart. At the initial stage of the war in the west (against France) decided to concentrate about 80% of Germany's armed forces, and the rest - in the east (against Russia). The attack on France was supposed to strike through neutral Belgium to the north of Paris, bypassing the main forces of the French army. As a result of this strategic maneuver ("indirect attack") the Germans intended to encircle and destroy the French army before Russia completes mobilization. After the defeat within 4-6 weeks of the French army Germany had to transfer troops to the east and in the course of a blitzkrieg to defeat Russia.

In the early days of the war, German troops took the fortress of Liege and the capital Brussels. Then they unexpectedly fierce resistance narazylysya Belgians. Began the punitive operations against the local population. Do not hesitate any means, the German command armies drove westward. On the French-Belgian border, the first victorious battle with the French, which gave the Germans confidence. Opened the way to Paris. The French government left the capital and moved to Bordeaux.

Strategic plans of the German command seemed satisfied. Two German army corps and cavalry division was transferred to the east of Prussia, which already advancing Russian army under General Rennenkampf and Samson. But this assistance proved unnecessary because the Russians already failed and in September were driven from East Prussia. At the same time 30 thousand. Soldiers were surrounded and General Samsonov shot himself.

Instead, successful were the actions of the Russian Southwestern Front, which operated in August and September against Austria-Hungary. After the initial success of the Austro-Hungarian army suffered defeat after defeat. The Russian Army and the Brusilov Ruza resulting Galician battle captured Lviv, besieged fortress of Przemysl, occupied almost all of Galicia and Bukovina came to the Carpathian passes.

After the victory in the Battle of Galicia the Russians have opened up opportunities to invade Hungary, or direct blow straight from Poland to Berlin. At the insistence of the Allies, Russians hit in Germany. At the same time the German command concentrated its forces for an attack on Warsaw to distract the Russians and their allies to save the Austrians. As a result, German and Russian troops converged on a front of 300 km in the region of Ivangorod and Warsaw. The Russians, having outnumbered, defeated two armies of the enemy. Road to Berlin and Vienna was opened. The situation is saved by German generals P. von Hindenburg and his young colleague E.Lyudendorf. Skillful maneuvers, but at the cost of significant losses, they were able to prevent the Russian invasion.

Meanwhile, September 5-12 grand battle broke out in the north-east of Paris on the river Marne. The German command, believing that the French are incapable of doing serious opposition decided not to bypass Paris from the north, as was predicted Schlieffen Plan and piyty straight. But on the river Marne German troops encountered strong resistance to the French, who in a short time managed to collect in the right place considerable force (in the roll-over French forces at the front vylyku ​​role played by Parisian taxi drivers). The German offensive stopped. There was, as they say the French, the "miracle of the Marne." Plan blitzkrieg failed. However, German commanders assessed the situation as a temporary setback and planned to flank attack with a view to encircle the French and capture Paris. But the French and British troops who came to the front, suddenly attacked. Each side tried to get around the flanks of the enemy that looked like "Race to the Sea". Front Line vydovzhuvalas and reached 600 kilometers - from the borders of Switzerland to the English Channel. The front stabilized. This was an important strategic success of the Allies.

Before this war was shunting; now it has become the positional nature. Both soldiers are buried in trenches, which were built before the excavation and concrete fortifications are not available even for the heavy artillery. Before the trenches and mine fields and rows of wire obstacles. To overcome this defense, because of the then tactics and technical equipment of troops needed human resources.

Neither party had sufficient means to irrevocably change the course of events. So hopes were pinned to the aid of allies and to achieve success in other theaters of war.

The first could bring Japan into the war, which was on the side of the Entente. She captured German colonies in China and the Pacific. Entente countries demanded the involvement of Japanese soldiers fighting in Europe, but the Japanese government refused.

Germany supported the Ottoman Empire. To speed up the entry of Turkey into the war, the German ship "Geben" and "Breslau" under the Turkish flag bombarded Odessa, Sevastopol and other cities. This has caused a formation of new fronts. Russo-Turkish front in the Caucasus stretches for 350 km. You attack the Turks failed. In Sarykamyskiy battle (December 1914 - January 1915), the main forces of the Turkish army was defeated. Russian troops entered the territory of Turkey. The blame for the defeat of the Turkish leadership has put on the Armenians, who allegedly welcomed the victory of the Russians. Were arranged antyvirmenski pogroms. At the end of 1915 of 2.1 million Armenians in Turkey 600 thousand remained. This genocide of humanity is not yet known. It was the first precedent that train a whole series of mass killings of innocent people on a national basis, which brought the twentieth century. One of the reasons to hate Turks, Armenians were: religious intolerance (Armenians, Christians, Turks - Muslims), the dominance of Armenians in the economic life of the Empire (80% domestic and 50% of foreign trade was in their hands).

The front line was extended through Palestine and Mesopotamia, where the Turkish army faced with the British.

Failures befell the Austrian army in the Balkans, which has twice Belgrade Serbs but not surrendered and forced the Austrians out of the country.

Fighting in the western and eastern fronts meant the failure of the German plan for a blitzkrieg. War was writing a protracted and grow in scale. But such a war neither side was ready. Now the fate of war virishuvav no longer front and rear (economic and human potential).

In 1915 on the Western Front, Germany did not conduct active offensive operations. German troops fought a bloody but unsuccessful attack the French in Artois and Champagne. Last year France lost 1 million 292 thousand. Soldiers, the British - 279 thousand. Germans - 612 thousand. Holding back the offensive, the Germans swift counterattack nullify the enemy's progress. During one of the attacks of April 22 near the Belgian town of Ypres the Germans for the first time in world history, made a successful gas attack (the first use of chemical weapons took place in February 1915 Germans in Warsaw, but failed). With 15 thousand. British soldiers poisoned by chlorine-third died. This event demonstrated disregard of international law (in the 1907 Hague International Conference adopted the Convention on the Prohibition of Chemical Weapons) and marked the emergence of a new type of weapon. The troops were introduced masks.

For its part, the British and French tried to block the Strait of Bosporus and Dardanelles. And landing troops in April 1915 was unsuccessful. Turkish troops completely blocked the landing allies, who in December of that year, was forced to leave his bridgehead.

In those days ended with the April talks Entente and Italy. According to the London Agreement Italy joined the war against Germany. For this, after the war it had to depart Trieste and other Austrian regions of the Italian population, under the protectorate of Italy fell into Albania. A month later, Italy entered the war, but led her sprokvola. Italian troops resisted the 10 Austrian divisions.

It was the only relief for Russia, since a lot of the scale fighting in 1915 took place in the east. At the suggestion of the German Eastern Front commander, General von Hindenburg was directed against the brunt of Germany. Russian troops still conducted offensive operations not achieve the strategic benefits, but in order to alleviate the situation of the Allies in the west. Because of constant relocation connections and disparate actions firepower of the Russian armies remained low. Techno-economic backwardness of the plight led on the front. Not enough weapons, ammunition, uniforms, medicines. In Germany knew about the intentions of the Russian command, the strengths and vulnerabilities of the Russians. German and Austrian spies were in the Russian headquarters, even in the War Department and royal surroundings. Russia considered the weakest link of the Entente that it is easy to get to get out of the war.

May 2, 1915 after a preparatory bombardment by German and Austrian troops attacked and broke through the Russian defense. Over the next five months, they seized Galicia, Bukovina, part of Volhynia, Poland, Lithuania, Latvia and Belarus part. N losses struck 850 thousand. Killed and wounded, 900 thousand. Prisoners. Although Russia has not surrendered, the German High Command believed that the Russian army is not capable of serious offensive. The front stretching from the Gulf of Riga to the borders of Romania. Then, in the east also turned to trench warfare.

The successes of the German army pushed to intervene in the war and Bulgaria (Fall 1915). Formed Quadruple Alliance of Germany, Austria-Hungary, Turkey and Bulgaria. After the Bulgarian territory, Turkey is now able to communicate with its allies. However, a small Serbian army in October 1915 moved the German, Austro-Hungarian and Bulgarian troops. Russia could not provide assistance to Serbia, and the French and British troops arrived too late: the Serbian army had been defeated. Newly established Balkan front fighting until the middle of 1918 almost was not conducted.

So in 1915 a decisive victory not won any of coalitions. However, while working on the Entente, which had a strong industrial capacity and more human resources. They have established a large military manufacturing and built up a strategic advantage. The concentration of German troops on the Eastern Front in western allies opened the opportunity for rest and regrouping for making decisive blow. On the eve of the campaign in 1916 England and France than in Germany, had a greater army, defense in depth, powerful artillery. The troops of the German allies were scattered on various fronts and were marked by high efficiency.