World War I

The most important naval engagement of the war was the Battle of Jutland, waged on May 31 and June 1, 1916, between the British Grand Fleet and the German High Seas Fleet. Although the British losses, both in ships and human lives, were greater than Germany's, the German fleet, having returned to home ports, did not venture to give battle again during the war, and the British retained their supremacy at sea. Nevertheless, during the remainder of the war, German cruisers managed to run the blockade of Germany, which the British had established from the outset of the war. The Germans sank considerable tonnage of Allied shipping in the North Atlantic and then returned to their bases. In 1917 the Germans again resorted to unrestricted submarine warfare, convinced that this method was the only one that would defeat Great Britain. The plan not only failed to force the capitulation of Great Britain, but also caused the United States to declare war against Germany. The attacks of German submarines on British convoys in the Atlantic and in the North Sea caused much loss of shipping. As a result, in April 1918 the British attempted to block the German submarine bases at Ostend (Oostende) and Zeebrugge in Belgium; they succeeded in partially blocking Zeebrugge by sinking three overage British cruisers in the harbour, but failed at Ostend. In October, however, British land forces, advancing through Belgium, took the two submarine bases and other Belgian ports.

By the terms of the armistice the Germans surrendered to the Allies most of their fleet, consisting of 10 battleships, 17 cruisers, 50 torpedo boats, and more than 100 submarines. All of the fleet with the exception of the submarines was interned at Scapa Flow in November 1918, with German captains and crews aboard. The Treaty of Versailles (1919), which ended the war, provided that all the interned ships become the permanent property of the Allies; that other warships still in German possession also be surrendered; and that the size of any future German navy be drastically limited. In reprisal against these terms, the Germans on June 21, 1919, scuttled their ships interned at Scapa Flow.

The total tonnage of Allied ships sunk by German submarines, surface craft, and mines was nearly 13 million; the largest tonnage sunk in any one year was about 6 million, in 1917.

World War I provided a great stimulus to the production and military use of aircraft, including the aeroplane and airship, or dirigible balloon, and the tethered balloon, and to the evolution of air warfare. Aircraft were used for two principal purposes: observation and bombing. For observation of stationary battlefronts extensive use was made by both belligerents of small tethered balloons; for scouting at sea, dirigible balloons were extensively used, and aeroplanes were used for scouting coastal waters. In connection with military operations on land, aeroplanes were used to observe the disposition of the troops and defences of the enemy and for bombing the enemy's lines or troops in action. A special feature of the war was the raids conducted by means of dirigibles or aeroplanes on important enemy centres far removed from the battlefront.

The first German aeroplane raid on Paris took place on August 30, 1914; and the first German air raid on England was on Dover on December 21, 1914. During 1915 and 1916 the German type of dirigible known as the zeppelin raided eastern England and London 60 times. The first German aeroplane raid on London took place on November 28, 1916, and such raids were frequent during the remainder of the war. The object of the German raids on England was to bring about withdrawal of British planes from the western front for the defence of the homeland; to handicap British industry; and to destroy the morale of the civilian population. The raids caused much loss of life and damage to property but accomplished little of military value.

From the middle of 1915 aerial combats between planes or squadrons of planes of the belligerents were common. The Germans had superiority in the air on the western front from about October 1915 to July 1916, when the supremacy passed to the British. Allied supremacy gradually increased thereafter and with the entrance of the United States into the war became overwhelming. In April 1918 the United States had three air squadrons at the front; by November 1918 it had 45 squadrons comprising nearly 800 planes and more than 1,200 officers. The total personnel of the American air service increased from about 1,200 at the outbreak of the war to nearly 200,000 at the end. Among the noted aeroplane fighters, or aces, were the American Eddie Rickenbacker, the Canadian William Avery Bishop, and the German Baron Manfred von Richthofen.

World War I began on July 28, 1914, with the declaration of war by Austria-Hungary on Serbia, and hostilities between the Allied and Central Powers continued until the signing of the armistice on November 11, 1918, a period of 4 years, 3 months, and 14 days. The aggregate direct war costs of all the belligerents amounted to about US$186 billion. Casualties in the land forces amounted to more than 37 million (see the accompanying table, World War I Casualties); in addition, close to 10 million deaths among the civilian populations were caused indirectly by the war. Despite worldwide hopes that the settlements arrived at after the war would restore world peace on a permanent basis, World War I actually provided the basis for an even more devastating conflict. The defeated Central Powers declared their acceptance of President Wilson's 14 points as the basis for the armistice and expected the Allies to utilize the principles of the 14 points as the foundation for the peace treaties. On the whole, however, the Allies came to the conference at Versailles and to the subsequent peace conferences with the determination to exact from the Central Powers reparations equal to the entire cost of the war, and to distribute among themselves territories and possessions of the defeated nations according to formulae arrived at secretly during the years 1915 to 1917, before the entry of the United States into the war. President Wilson, in the peace negotiations, at first insisted that the Paris Peace Conference accept the full programme laid out in the 14 points, but finally, in order to secure the support of the Allies for the all-important 14th point, which called for the creation of the League of Nations, he abandoned his insistence on some of the other points.

The peace treaties that emerged from the conferences at Versailles, Saint-Germain, Trianon, Neuilly, and Sèvres were on the whole inadequately enforced by the victorious powers, leading to the resurgence of militarism and aggressive nationalism in Germany and to social disorder throughout much of Europe.