Germany’s attack on France was launched across neutral Belgium. By September 1914, German troops had reached the Marne River near Paris. However, the French and British armies managed to hold the line, and Paris was saved. France’s success in the Battle of the Marne changed the entire nature of the war. Germany’s hope of swift victory ended. Both sides now dug trenches on the western front, which stretched from Switzerland to the shores of the North Sea. On the eastern front, the Russians were still completing mobilization. Responding to a plea by the French to divert German forces from the western front, the Russian army launched an attack toward the important German seaport of Danzig. In late August, the Russians met a German force in the Battle of Tannenberg, which is located in East Prussia.
The Russians suffered a humiliating defeat. Soon afterward the Germans launched an offensive in the east and crossed into Russian Poland. The war was fought outside of Europe also. Fighting took place in the Middle East, Africa, and in the Pacific. Fighting on Gallipoli. Although Russia had a huge army, it lacked enough guns and ammunition to equip its soldiers properly. In 1915 Great Britain and France decided to attempt to force their way through the Dardanelles so that they could capture Constantinople. They had hoped that this would remove the Ottoman Empire from the war and allow supplies to reach the Russians. The British and French had hoped that bombardment from their heavily armed battleships alone would destroy the Ottoman artillery on the Gallipoli Peninsula. When the bombardment failed after several days, however, they decided to land troops on the Gallipoli Peninsula. The Turks resisted stubbornly and the fighting became a stalemate.
After eight months of fighting and the loss of hundreds of thousands of lives on both sides, the Allies abandoned their plans to capture Constantinople and withdrew from Gallipoli. Naval warfare. The British decided to blockade the North Sea to keep merchant ships from reaching Germany. Originally, they set up the blockade to prevent the Germans from getting raw materials to manufacture war equipment. Gradually, however, the blockade became an attempt to ruin the German economy and starve the German people. Germany also set up a blockade. Employing its fleet of U-boats, it attempted to win the war by sinking ships carrying food and munitions to the British. In May 1915, without warning, a German submarine sank the British passenger liner Lusitania off the coast of Ireland.
The sinking of the Lusitania, which was carrying passengers as well as a cargo of war materials to England, killed nearly 1,200 people, including more than 100 Americans. Woodrow Wilson, the U.S. president, warned Germany that the United States would not tolerate another such incident. For the next year and a half, Germany used submarine warfare only sparingly. It did not wish to provoke the neutral Americans into entering the war. In May 1916, the only large naval battle of the war was fought by Germany and Britain in the North Sea off the coast of Jutland, Denmark. Although both sides claimed they had won a victory, the German navy did, however, retire to port, where it remained for the rest of the war.