The outbreak of war
With Serbia already much aggrandized by the two Balkan Wars (1912â13, 1913), Serbian nationalists turned their attention back to the idea of "liberating" the South Slavs of Austria-Hungary. Colonel Dragutin DimitrijeviÄ, head of Serbia's military intelligence, was also, under the alias "Apis," head of the secret society Union or Death, pledged to the pursuit of this pan-Serbian ambition. Believing that the Serbs' cause would be served by the death of the Austrian archduke Franz Ferdinand, heir presumptive to the Austrian emperor Franz Joseph, and learning that the Archduke was about to visit Bosnia on a tour of military inspection, Apis plotted his assassination. Nikola PaĆĄiÄ, the Serbian prime minister and an enemy of Apis, heard of the plot and warned the Austrian government of it, but his message was too cautiously worded to be understood.
Archduke Franz Ferdinand and his wife, Sophie, duchess of Hohenberg
Archduke Franz Ferdinand and his wife, Sophie, duchess of Hohenberg
At 11:15 AM on June 28, 1914, in the Bosnian capital, Sarajevo, Franz Ferdinand and his morganatic wife, Sophie, duchess of Hohenberg, were shot dead by a Bosnian Serb, Gavrilo Princip. The chief of the Austro-Hungarian general staff, Franz, Graf (count) Conrad von Hötzendorf, and the foreign minister, Leopold, Graf von Berchtold, saw the crime as the occasion for measures to humiliate Serbia and so to enhance Austria-Hungary's prestige in the Balkans. Conrad had already (October 1913) been assured by William II of Germany's support if Austria-Hungary should start a preventive war against Serbia. This assurance was confirmed in the week following the assassination, before William, on July 6, set off upon his annual cruise to the North Cape, off Norway.
Louis IX of France (St. Louis), stained glass window of Louis IX during the Crusades. (Unknown location.)
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The Austrians decided to present an unacceptable ultimatum to Serbia and then to declare war, relying on Germany to deter Russia from intervention. Though the terms of the ultimatum were finally approved on July 19, its delivery was postponed to the evening of July 23, since by that time the French president, Raymond Poincaré, and his premier, René Viviani, who had set off on a state visit to Russia on July 15, would be on their way home and therefore unable to concert an immediate reaction with their Russian allies. When the delivery was announced, on July 24, Russia declared that Austria-Hungary must not be allowed to crush Serbia.
Serbia replied to the ultimatum on July 25, accepting most of its demands but protesting against two of themânamely, that Serbian officials (unnamed) should be dismissed at Austria-Hungary's behest and that Austro-Hungarian officials should take part, on Serbian soil, in proceedings against organizations hostile to Austria-Hungary. Though Serbia offered to submit the issue to international arbitration, Austria-Hungary promptly severed diplomatic relations and ordered partial mobilization.
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Home from his cruise on July 27, William learned on July 28 how Serbia had replied to the ultimatum. At once he instructed the German Foreign Office to tell Austria-Hungary that there was no longer any justification for war and that it should content itself with a temporary occupation of Belgrade. But, meanwhile, the German Foreign Office had been giving such encouragement to Berchtold that already on July 27 he had persuaded Franz Joseph to authorize war against Serbia. War was in fact declared on July 28, and Austro-Hungarian artillery began to bombard Belgrade the next day. Russia then ordered partial mobilization against Austria-Hungary, and on July 30, when Austria-Hungary was riposting conventionally with an order of mobilization on its Russian frontier, Russia ordered general mobilization. Germany, which since July 28 had still been hoping, in disregard of earlier warning hints from Great Britain, that Austria-Hungary's war against Serbia could be "localized" to the Balkans, was now disillusioned insofar as eastern Europe was concerned. On July 31 Germany sent a 24-hour ultimatum requiring Russia to halt its mobilization and an 18-hour ultimatum requiring France to promise neutrality in the event of war between Russia and Germany.
Both Russia and France predictably ignored these demands. On August 1 Germany ordered general mobilization and declared war against Russia, and France likewise ordered general mobilization. The next day Germany sent troops into Luxembourg and demanded from Belgium free passage for German troops across its neutral territory. On August 3 Germany declared war against France.
In the night of August 3â4 German forces invaded Belgium. Thereupon, Great Britain, which had no concern with Serbia and no express obligation to fight either for Russia or for France but was expressly committed to defend Belgium, on August 4 declared war against Germany.
Austria-Hungary declared war against Russia on August 5; Serbia against Germany on August 6; Montenegro against Austria-Hungary on August 7 and against Germany on August 12; France and Great Britain against Austria-Hungary on August 10 and on August 12, respectively; Japan against Germany on August 23; Austria-Hungary against Japan on August 25 and against Belgium on August 28.
Romania had renewed its secret anti-Russian alliance of 1883 with the Central Powers on February 26, 1914, but now chose to remain neutral. Italy had confirmed the Triple Alliance on December 7, 1912, but could now propound formal arguments for disregarding it: first, Italy was not obliged to support its allies in a war of aggression; second, the original treaty of 1882 had stated expressly that the alliance was not against England.
On September 5, 1914, Russia, France, and Great Britain concluded the Treaty of London, each promising not to make a separate peace with the Central Powers. Thenceforth, they could be called the Allied, or Entente, powers, or simply the Allies.
Witness the beginning of World War I with the assassination of Archduke Franz Ferdinand on June 28, 1914
Witness the beginning of World War I with the assassination of Archduke Franz Ferdinand on June 28, 1914See all videos for this article
The outbreak of war in August 1914 was generally greeted with confidence and jubilation by the peoples of Europe, among whom it inspired a wave of patriotic feeling and celebration. Few people imagined how long or how disastrous a war between the great nations of Europe could be, and most believed that their country's side would be victorious within a matter of months. The war was welcomed either patriotically, as a defensive one imposed by national necessity, or idealistically, as one for upholding right against might, the sanctity of treaties, and international morality.
Forces and resources of the combatant nations in 1914
When war broke out, the Allied powers possessed greater overall demographic, industrial, and military resources than the Central Powers and enjoyed easier access to the oceans for trade with neutral countries, particularly with the United States.
Table 1 shows the population, steel production, and armed strengths of the two rival coalitions in 1914.
Strength of the belligerents, Aug. 4, 1914
resources Central Powers Allied Powers
population (in millions) 115.2 265.5
steel production (in millions of metric tons) 17.0 15.3
army divisions available for mobilization 146 212
modern battleships 20 39
All the initial belligerents in World War I were self-sufficient in food except Great Britain and Germany. Great Britain's industrial establishment was slightly superior to Germany's (17 percent of world trade in 1913 as compared with 12 percent for Germany), but Germany's diversified chemical industry facilitated the production of ersatz, or substitute, materials, which compensated for the worst shortages ensuing from the British wartime blockade. The German chemist Fritz Haber was already developing a process for the fixation of nitrogen from air; this process made Germany self-sufficient in explosives and thus no longer dependent on imports of nitrates from Chile.
Of all the initial belligerent nations, only Great Britain had a volunteer army, and this was quite small at the start of the war. The other nations had much larger conscript armies that required three to four years of service from able-bodied males of military age, to be followed by several years in reserve formations. Military strength on land was counted in terms of divisions composed of 12,000â20,000 officers and men. Two or more divisions made up an army corps, and two or more corps made up an army. An army could thus comprise anywhere from 50,000 to 250,000 men.
WORLD WAR I EVENTS
World War I
Battle of the Frontiers
August 4, 1914 - September 6, 1914
Western Front; World War I
Battle of Mons
August 23, 1914
Battle of Tannenberg
Battle of Tannenberg
August 26, 1914 - August 30, 1914
World War I
First Battle of the Marne
September 6, 1914 - September 12, 1914
Ypres, Belgium
First Battle of Ypres
October 19, 1914 - November 22, 1914
default image
Battle of Tanga
November 2, 1914 - November 5, 1914
Falkland Islands Map
Battle of the Falkland Islands
December 8, 1914
Christmas Truce
Christmas Truce
December 24, 1914 - December 25, 1914
World War I: Allied troops on the Gallipoli Peninsula
Gallipoli Campaign
February 16, 1915 - January 9, 1916
Dardanelles
Naval Operations in the Dardanelles Campaign
February 19, 1915 - March 18, 1915
gas masks at the Second Battle of Ypres
Second Battle of Ypres
April 22, 1915 - May 25, 1915
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Battles of the Isonzo
June 23, 1915 - October 24, 1917
Australia and New Zealand Army Corps troops
Battle of Lone Pine
August 6, 1915 - August 10, 1915
Battle of Verdun
Battle of Verdun
February 21, 1916 - December 18, 1916
Battle of Jutland
Battle of Jutland
May 31, 1916 - June 1, 1916
Aleksey A. Brusilov
Brusilov Offensive
June 4, 1916 - August 10, 1916
Somme; machine gun
First Battle of the Somme
July 1, 1916 - November 13, 1916
Cloth Hall; Battle of Ypres
Battle of Messines
June 7, 1917 - June 14, 1917
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June Offensive
July 1, 1917 - c. July 4, 1917
Ypres, Belgium, 1918
Battle of Passchendaele
July 31, 1917 - November 6, 1917
Cadorna, Luigi
Battle of Caporetto
October 24, 1917 - December 19, 1917
Cambrai, Battle of; tank
Battle of Cambrai
November 20, 1917 - December 8, 1917
treaties of Brest-Litovsk
treaties of Brest-Litovsk
February 9, 1918; March 3, 1918
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Battle of Belleau Wood
June 1, 1918 - June 26, 1918
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Battle of Amiens
August 8, 1918 - August 11, 1918
Pershing, John J.
Battle of Saint-Mihiel
September 12, 1918 - September 16, 1918
World War I: British army
Battle of Cambrai
September 27, 1918 - October 11, 1918
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Battle of Mons
November 11, 1918
The land forces of the belligerent nations at the outbreak of war in August 1914 are shown in Table 2.
Land forces of the belligerents, Aug. 4, 1914
country regular divisions (with number of field armies) other land forces total manpower
*Restricted in 1914 to service at home.
Central Powers Germany 98 (8) 27 Landwehr brigades 1,900,000
Austria-Hungary 48 (6) 450,000
Allied Powers Russia 102 (6) 1,400,000
France 72 (5) 1,290,000
Serbia 11 (3) 190,000
Belgium 7 (1) 69,000 fortress troops 186,000
Great Britain 6 (1) 14 territorial divisions* 120,000
The higher state of discipline, training, leadership, and armament of the German army reduced the importance of the initial numerical inferiority of the armies of the Central Powers. Because of the comparative slowness of mobilization, poor higher leadership, and lower scale of armament of the Russian armies, there was an approximate balance of forces between the Central Powers and the Allies in August 1914 that prevented either side from gaining a quick victory.
Germany and Austria also enjoyed the advantage of "interior lines of communication," which enabled them to send their forces to critical points on the battlefronts by the shortest route. According to one estimate, Germany's railway network made it possible to move eight divisions simultaneously from the Western Front to the Eastern Front in four and a half days.
Even greater in importance was the advantage that Germany derived from its strong military traditions and its cadre of highly efficient and disciplined regular officers. Skilled in directing a war of movement and quick to exploit the advantages of flank attacks, German senior officers were to prove generally more capable than their Allied counterparts at directing the operations of large troop formations.
Sea power was largely reckoned in terms of capital ships, or dreadnought battleships and battle cruisers having extremely large guns. Despite intensive competition from the Germans, the British had maintained their superiority in numbers, with the result that, in capital ships, the Allies had an almost two-to-one advantage over the Central Powers.
The strength of the two principal rivals at sea, Great Britain and Germany, is compared in Table 3.
British and German naval strength, August 1914
type British German
*Including Canadian, Australian, and New Zealand destroyers of all classes.
dreadnought battleships 20 14
battle cruisers 9 4
pre-dreadnought battleships 39 22
armoured cruisers 34 9
cruisers 64 41
destroyers 301* 144
submarines 65 28
The numerical superiority of the British navy, however, was offset by the technological lead of the German navy in many categories, such as range-finding equipment, magazine protection, searchlights, torpedoes, and mines. Great Britain relied on the Royal Navy not only to ensure necessary imports of food and other supplies in wartime but also to sever the Central Powers' access to the markets of the world. With superior numbers of warships, Great Britain could impose a blockade that gradually weakened Germany by preventing imports from overseas.