1914
| Dates | Events | |
|---|---|---|
| June 28 | Assassination of Archduke Franz Ferdinand of Austria, the heir to the Austro-Hungarian throne, who is killed in Sarajevo along with his wife, Duchess Sophie. | Details |
| July 5 | Austria-Hungary seeks German support for a war against Serbia in case of Russian militarism. Germany gives assurances of support. | |
| July 23 | Austria-Hungary sends an ultimatum to Serbia. The Serbian response is seen as unsatisfactory. | Details |
| July 28 | Austria-Hungary declares war on Serbia. Russia mobilizes. | |
| July 31 | Germany warns Russia to stop mobilizing. Russia says mobilization is against Austria-Hungary only. | |
| August 1 | Germany declares war on Russia. | |
| Italy declares its neutrality. Germany and the Ottoman Empire sign a secret alliance treaty. |
Details | |
| August 2 | Germany invades Luxembourg. | Details |
| August 3 | Germany declares war on France and Belgium. | |
| August 4 | Germany invades Belgium to outflank the French army. | Details |
| Britain protests the violation of Belgian neutrality, guaranteed by a treaty; German Chancellor replies that the treaty is just a chiffon de papier (a scrap of paper). The United Kingdom declares war on Germany. |
Details | |
| August 5 | Montenegro declares war on Austria-Hungary. | |
| The Ottoman Empire closes the Dardanelles. | ||
| August 5–August 16 | The Germans besiege and then capture the fortresses of Liège, Belgium. | Details |
| August 6 | Austria-Hungary declares war on Russia. Serbia declares war on Germany. |
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| August 7 | The British Expeditionary Force arrives in France. | Details |
| August 9 | Montenegro declares war on Germany. | |
| August 11 | France declares war on Austria-Hungary. | |
| August 12 | The United Kingdom declares war on Austria-Hungary. | |
| August 14–August 24 | Battle of the Frontiers. The Germans obtain a victory against the British Expeditionary Force and France's Fifth Army. | Details |
| August 16–August 19 | The Serbs defeat the Austro-Hungarians at the Battle of Cer. | Details |
| August 17 | The Russian army enters East Prussia. Battle of Stalluponen. | Details |
| August 20 | The Germans attack the Russians in East Prussia. The attack is a failure in addition to being a deviation from the Schlieffen Plan. | Details |
| August 17–September 2 | Battle of Tannenberg: the Russian army undergoes a heavy defeat by the Germans. | Details |
| August 20 | The Germans occupy Brussels. | |
| August 22 | Austria-Hungary declares war on Belgium. | |
| August 23 | Japan declares war on Germany. | Details |
| August 23–August 25 | Battle of Kraśnik. The Austro-Hungarian First Army defeats the Russian Fourth Army. | Details |
| August 24–September 7 | The Germans siege and capture the Maubeuge Fortress. | Details |
| August 25 | Japan declares war on Austria-Hungary. | |
| August 26 | British and French forces conquer Togoland, a German protectorate in West Africa. | Details |
| August 26–August 27 | Battle of Le Cateau. Allied retreat. | Details |
| August 26–September 11 | Battle of Lemberg. The Russians capture Lviv. | Details |
| August 27–November 7 | Battle of Tsingtao: British and Japanese forces capture the German-controlled port of Tsingtao in China. | Details |
| August 28 | The Royal Navy wins the First Battle of Heligoland Bight, North Sea. | Details |
| August 29–August 30 | Battle of Saint Quentin, aka Battle of Guise. Orderly Allied retreat. | Details |
| August 30 | New Zealand occupies German Samoa (later Western Samoa). | Details |
| September 3–September 11 | Austro-Hungarian defeat at the Battle of Rava Russka. | Details |
| September 5–September 12 | First Battle of the Marne. The German advance on Paris is halted, marking the failure of the Schlieffen Plan. | Details |
| September 7–September 14 | First Battle of the Masurian Lakes: The Russian Army of the Neman withdraws from East Prussia with heavy casualties. | Details |
| September 8–September 17 | Second Austro-Hungarian attempt at invading Serbia fails. | |
| September 9 | Theobald von Bethmann Hollweg lays out Germany's war aims. | Details |
| September 11–September 11 | Australian forces occupy German New Guinea. | Details |
| September 13 | Troops from South Africa begin invading German South-West Africa. | Details |
| September 13–September 28 | The First Battle of the Aisne ends in a substantial draw. The Race to the Sea begins. | Details |
| September 14 | Erich von Falkenhayn replaces Helmuth von Moltke the Younger as German Chief of Staff. | Details |
| September 17 | The Siege of Przemyśl begins | Details |
| September 28–October 10 | The Germans siege and capture Antwerp, Belgium. | Details |
| September 29–October 31 | Battle of the Vistula, aka Battle of Warsaw. | Details |
| October 16–October 31 | Battle of the Yser. French and Belgian forces secure the coastline of Belgium. | Details |
| October 19–November 22 | The First Battle of Ypres ends the Race to the Sea. The Germans are prevented from reaching Calais and Dunkirk. | Details |
| November 1 | Russia declares war on the Ottoman Empire. | |
| Battle of Coronel. Von Spee's German cruiser squadron defeats a Royal Navy squadron under Christopher Cradock. | Details | |
| November 2 | The United Kingdom begins the naval blockade of Germany. | Details |
| November 3 | Montenegro declares war on the Ottoman Empire. | |
| November 3–November 5 | Von Lettow-Vorbeck's German colonial forces defeat the British at the Battle of Tanga, German East Africa. | Details |
| November 5 | France and the United Kingdom declare war on the Ottoman Empire. | |
| November 6 | The Austro-Hungarians enter Belgrade. | Details |
| November 9 | Battle of Cocos, northeast Indian Ocean. The Australian cruiser Sydney destroys the German cruiser Emden. | Details |
| November 11–December 6 | Battle of Łódź | Details |
| November 11 | Sultan Mehmed V declares Jihad on the Allies. | Details |
| December 8 | Battle of the Falklands. Von Spee's German cruiser squadron is defeated by the Royal Navy. | Details |
| December 16 | The German fleet shells Scarborough and Hartlepool, England. | Details |
| December 24-December 25 | In some sectors of the Western Front, an unofficial Christmas truce is observed between German and British forces. | Details |
| December 29–January 2, 1915 | The Russians win the Battle of Sarikamis, Caucasia. | Details |
Read more about this topic: Timeline Of World War I