World War I: Battle of Jutland: The British Grand Fleet under the command of John Jellicoe, 1st Earl Jellicoe and David Beatty, 1st Earl Beatty engage the Imperial German Navy under the command of Reinhard Scheer and Franz von Hipper in the largest naval battle of the war, which proves indecisive.

The Battle of Jutland (German: Skagerrakschlacht, the Battle of Skagerrak) was a naval battle fought between Britain's Royal Navy Grand Fleet, under Admiral Sir John Jellicoe, and the Imperial German Navy's High Seas Fleet, under Vice-Admiral Reinhard Scheer, during the First World War. The battle unfolded in extensive manoeuvring and three main engagements (the battlecruiser action, the fleet action and the night action), from 31 May to 1 June 1916, off the North Sea coast of Denmark's Jutland Peninsula. It was the largest naval battle and the only full-scale clash of battleships in that war. Jutland was the third fleet action between steel battleships, following the Battle of the Yellow Sea in 1904 and the decisive Battle of Tsushima in 1905, during the Russo-Japanese War. Jutland was the last major battle in world history fought primarily by battleships.Germany's High Seas Fleet intended to lure out, trap, and destroy a portion of the Grand Fleet, as the German naval force was insufficient to openly engage the entire British fleet. This formed part of a larger strategy to break the British blockade of Germany and to allow German naval vessels access to the Atlantic. Meanwhile, Great Britain's Royal Navy pursued a strategy of engaging and destroying the High Seas Fleet, thereby keeping German naval forces contained and away from Britain and her shipping lanes.The Germans planned to use Vice-Admiral Franz Hipper's fast scouting group of five modern battlecruisers to lure Vice-Admiral Sir David Beatty's battlecruiser squadrons into the path of the main German fleet. They stationed submarines in advance across the likely routes of the British ships. However, the British learned from signal intercepts that a major fleet operation was likely, so on 30 May Jellicoe sailed with the Grand Fleet to rendezvous with Beatty, passing over the locations of the German submarine picket lines while they were unprepared. The German plan had been delayed, causing further problems for their submarines, which had reached the limit of their endurance at sea.

On the afternoon of 31 May, Beatty encountered Hipper's battlecruiser force long before the Germans had expected. In a running battle, Hipper successfully drew the British vanguard into the path of the High Seas Fleet. By the time Beatty sighted the larger force and turned back towards the British main fleet, he had lost two battlecruisers from a force of six battlecruisers and four powerful battleshipsthough he had sped ahead of his battleships of 5th Battle Squadron earlier in the day, effectively losing them as an integral component for much of this opening action against the five ships commanded by Hipper. Beatty's withdrawal at the sight of the High Seas Fleet, which the British had not known were in the open sea, would reverse the course of the battle by drawing the German fleet in pursuit towards the British Grand Fleet. Between 18:30, when the sun was lowering on the western horizon, back-lighting the German forces, and nightfall at about 20:30, the two fleetstotalling 250 ships between themdirectly engaged twice.

Fourteen British and eleven German ships sank, with a total of 9,823 casualties. After sunset, and throughout the night, Jellicoe manoeuvred to cut the Germans off from their base, hoping to continue the battle the next morning, but under the cover of darkness Scheer broke through the British light forces forming the rearguard of the Grand Fleet and returned to port.Both sides claimed victory. The British lost more ships and twice as many sailors but succeeded in containing the German fleet. The British press criticised the Grand Fleet's failure to force a decisive outcome, while Scheer's plan of destroying a substantial portion of the British fleet also failed. The British strategy of denying Germany access to both the United Kingdom and the Atlantic did succeed, which was the British long-term goal. The Germans' "fleet in being" continued to pose a threat, requiring the British to keep their battleships concentrated in the North Sea, but the battle reinforced the German policy of avoiding all fleet-to-fleet contact. At the end of 1916, after further unsuccessful attempts to reduce the Royal Navy's numerical advantage, the German Navy accepted that its surface ships had been successfully contained, subsequently turning its efforts and resources to unrestricted submarine warfare and the destruction of Allied and neutral shipping, whichalong with the Zimmermann Telegramby April 1917 triggered the United States of America's declaration of war on Germany.Subsequent reviews commissioned by the Royal Navy generated strong disagreement between supporters of Jellicoe and Beatty concerning the two admirals' performance in the battle. Debate over their performance and the significance of the battle continues to this day.

World War I, often abbreviated as WWI or WW1, also known as the First World War and contemporaneously known as the Great War and by other names, was an international conflict that began on 28 July 1914 and ended on 11 November 1918. It involved much of Europe, as well as Russia, the United States and Turkey, and was also fought in the Middle East, Africa and parts of Asia. One of the deadliest conflicts in history, an estimated 9 million were killed in combat, while over 5 million civilians died from occupation, bombardment, hunger or disease. The genocides perpetrated by the Ottomans and the 1918 Spanish flu pandemic spread by the movement of combatants during the war caused many millions of additional deaths worldwide.In 1914, the Great Powers were divided into two opposing alliances: the Triple Entente, consisting of France, Russia, and Britain, and the Triple Alliance, made up of Germany, Austria-Hungary, and Italy. Tensions in the Balkans came to a head on 28 June 1914 following the assassination of Archduke Franz Ferdinand, the Austro-Hungarian heir, by Gavrilo Princip, a Bosnian Serb. Austria-Hungary blamed Serbia and the interlocking alliances involved the Powers in a series of diplomatic exchanges known as the July Crisis. On 28 July, Austria-Hungary declared war on Serbia; Russia came to Serbia's defence and by 4 August, the conflict had expanded to include Germany, France and Britain, along with their respective colonial empires. In November, the Ottoman Empire, Germany and Austria formed the Central Powers, while in April 1915, Italy joined Britain, France, Russia and Serbia as the Allied Powers.

Facing a war on two fronts, German strategy in 1914 was to defeat France, then shift its forces to the East and knock out Russia, commonly known as the Schlieffen Plan. This failed when their advance into France was halted at the Marne; by the end of 1914, the two sides faced each other along the Western Front, a continuous series of trench lines stretching from the Channel to Switzerland that changed little until 1917. By contrast, the Eastern Front was far more fluid, with Austria-Hungary and Russia gaining, then losing large swathes of territory. Other significant theatres included the Middle East, the Alpine Front and the Balkans, bringing Bulgaria, Romania and Greece into the war.

Shortages caused by the Allied naval blockade led Germany to initiate unrestricted submarine warfare in early 1917, bringing the previously neutral United States into the war on 6 April 1917. In Russia, the Bolsheviks seized power in the 1917 October Revolution and made peace in the March 1918 Treaty of Brest-Litovsk, freeing up large numbers of German troops. By transferring these to the Western Front, the German General Staff hoped to win a decisive victory before American reinforcements could impact the war, and launched the March 1918 German spring offensive. Despite initial success, it was soon halted by heavy casualties and ferocious defence; in August, the Allies launched the Hundred Days Offensive and although the German army continued to fight hard, it could no longer halt their advance.Towards the end of 1918, the Central Powers began to collapse; Bulgaria signed an Armistice on 29 September, followed by the Ottomans on 31 October, then Austria-Hungary on 3 November. Isolated, facing revolution at home and an army on the verge of mutiny, Kaiser Wilhelm abdicated on 9 November and the new German government signed the Armistice of 11 November 1918, bringing the fighting to a close. The 1919 Paris Peace Conference imposed various settlements on the defeated powers, the best known being the Treaty of Versailles. The dissolution of the Russian, German, Ottoman and Austro-Hungarian empires led to numerous uprisings and the creation of independent states, including Poland, Czechoslovakia and Yugoslavia. For reasons that are still debated, failure to manage the instability that resulted from this upheaval during the interwar period ended with the outbreak of World War II in 1939.