|Dec 25-Jan 18, 1915||Battle of Ardahan.|
|Dec 24-Dec 25||In some sectors of the Western Front, an unofficial Christmas truce is observed between German and British forces. Details|
|Dec 22-Jan 2, 1915||The Russians win the Battle of Sarikamis, Caucasia. Details|
|Dec 22||Fighting begins at Noyon.|
|Dec 20-17 March 1915||First Battle of Champagne. Details |
|Dec 20||Fighting begins at Perthes. Details|
|Dec 18-Dec 22||Battle of Givenchy. |
|Dec 16||The German fleet shells Scarborough and Hartlepool, England. Details|
|Dec 10||Hill 60 captured by the Germans. Details|
|Dec 8||Battle of the Falklands. Von Spee's German cruiser squadron is defeated by the Royal Navy. Details|
|Dec 3-Dec 9||Battle of Qurna. |
|Dec 1-Dec 13||Battle of Limanowa. |
|Dec-Jan, 1915||First Battle of Artois. |
|Nov 16-Dec 15||Battle of Kolubara, Austro-Hungarians leave Serbia. |
|Nov 11-Dec 6||Battle of Lódz (aka Silesian Offensive). Details|
|Nov 11-Nov 21||Battle of Basra. Details|
|Nov 11||Sultan Mehmed V declares Jihad on the Allies. Details|
|Nov 9||Battle of Cocos, northeast Indian Ocean. The Australian cruiser Sydney destroys the German cruiser Emden. Details|
|Nov 6||Fao Landing, British and Indians besiege the fortress at Fao. |
|Nov 5||France and the United Kingdom declare war on the Ottoman Empire. |
|Nov 3-Nov 5||Von Lettow-Vorbeck's German colonial forces defeat the British at the Battle of Tanga, German East Africa. Details|
|Nov 3||Montenegro declares war on the Ottoman Empire. |
Battle of Kilimanjaro.
|Nov 2-Nov 16||Bergmann Offensive, first military engagement in the Caucuses of the First World War. |
|Nov 2||The United Kingdom begins the naval blockade of Germany. Details|
|Nov 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
|Oct 19-Nov 22||The First Battle of Ypres ends the Race to the Sea. The Germans are prevented from reaching Calais and Dunkirk. Details|
|Oct 16-Oct 31||Battle of the Yser. French and Belgian forces secure the coastline of Belgium. Details
|Oct 13-Nov 2||Battle of Armentieres. |
|Oct 12-Nov 2||First Battle of Messines. Details|
|Oct 10-Nov 2||Battle of La Bassee. |
|Oct 9-Nov 1||Central powers control Belgrade. Details|
|Oct 1-Oct 4||First Battle of Arras. Details|
|Oct 1914-July 11, 1915||Battle of Rufiji Delta, German cruiser Königsberg destroyed. |
|Sept 29-Oct 31||Battle of the Vistula River, aka Battle of Warsaw. Details|
|Sept 28-Oct 10||The Germans besiege and capture Antwerp, Belgium. Details|
|Sept 25-Sept 29||First Battle of Albert Details|
|Sept 24||The Siege of Przemysl begins Details|
|Sept 22-Sept 26||First Battle of Picardy. |
|Sept 20||Battle of Zanzibar, German naval victory. |
|Sept 19-Oct 11||Battle of Flirey |
|Sept 14||Erich von Falkenhayn replaces Helmuth von Moltke the Younger as German Chief of Staff. Details|
|Sept 13-Sept 28||The First Battle of the Aisne ends in a substantial draw. The Race to the Sea begins. Details|
|Sept 13||Troops from South Africa begin invading German South-West Africa. Details|
|Sept 11||Australian forces occupy German New Guinea. Details|
|Sept 9||Theobald von Bethmann Hollweg lays out Germany's war aims. Details|
|Sept 7-Sept 14||First Battle of the Masurian Lakes: The Russian Army of the Neman withdraws from East Prussia with heavy casualties. Details|
|Sept 6-Oct 4||Battle of Drina. |
|Sept 6-Sept 12||Battle of the Marshes of Saint-Gond, a phase of the First Battle of the Marne. |
Battle of Vitry, a phase of the First Battle of the Marne.
Battle of Revigny, a phase of the First Battle of the Marne.
|Sept 5-Sept 12||First Battle of the Marne. The German advance on Paris is halted, marking the failure of the Schlieffen Plan. Details|
Battle of the Ourcq, a phase of the First Battle of the Marne.
Battle of the Two Morins.
|Sept 4-Sept 13||Battle of Grand Couronne, a phase of the Battle of the Frontiers. |
|Sept 2-Sept 11||Austro-Hungarian defeat at the Battle of Rava Russka, a phase of the Battle of Lemberg. Details|
|Sept 1||Action at Nery Details|
|Aug 30||New Zealand occupies German Samoa (later Western Samoa). Details|
|Aug 29-Aug 30||Battle of Saint Quentin, aka Battle of Guise. Orderly Allied retreat. Details|
|Aug 28||The Royal Navy wins the First Battle of Heligoland Bight, North Sea. Details|
|Aug 27-Nov 7||Battle of Tsingtao: British and Japanese forces capture the German-controlled port of Tsingtao in China. Details|
|Aug 27||Battle of Étreux. Details|
|Aug 26-Sept 2||Battle of Komarow, part of the Battle of Lemberg. Details|
|Aug 26-Aug 30||Battle of Gnila Lipa, a phase of the Battle of Lemberg. |
|Aug 26-Aug 27||Battle of Le Cateau. Allied retreat. Details|
|Aug 26||British and French forces conquer Togoland, a German protectorate in West Africa. Details|
Battle of Le Grand Fayt.
|Aug 25||Japan declares war on Austria-Hungary. |
|Aug 24-Sept 28||The Allied Great Retreat to the River Marne. |
|Aug 24-Sept 7||The Germans besiege and capture the Maubeuge Fortress. Details|
|Aug 24||Action of Elouges. |
Battle of the Mortagne, a phase of the Battle of Lorraine.
|Aug 23-Aug 25||Battle of Krasnik, a phase of the Battle of Lemberg. The Austro-Hungarian First Army defeats the Russian Fourth Army. Details|
|Aug 23-Sept 11||Battle of Lemberg. The Russians capture Lviv. Details|
|Aug 23-Aug 30||Battle of Tannenberg: the Russian army undergoes a heavy defeat by the Germans. Details|
|Aug 23||Japan declares war on Germany. Details|
Battle of Mons, a phase of the Battle of the Frontiers.
|Aug 22||Austria-Hungary declares war on Belgium. |
|Aug 21-Aug 23||Battle of the Ardennes, a phase of the Battle of the Frontiers. |
|Aug 21||Battle of Charleroi, a phase of the Battle of the Frontiers. |
|Aug 20||The Germans attack the Russians in East Prussia, the Battle of Gumbinnen. The attack is a failure in addition to being a deviation from the Schlieffen Plan. Details|
The Germans occupy Brussels.
Battle of Morhange, a phase of the Battle of Lorraine.
Battle of Sarrebourg, a phase of the Battle of Lorraine.
|Aug 17||The Russian army enters East Prussia. Battle of Stalluponen. Details|
|Aug 16-Aug 19||The Serbs defeat the Austro-Hungarians at the Battle of Cer. Details|
|Aug 14-Aug 25||Battle of Lorraine, a phase of the Battle of the Frontiers. |
|Aug 12||The United Kingdom declares war on Austria-Hungary. |
Battle of Haelen, a phase of the Battle of the Frontiers.
|Aug 11||France declares war on Austria-Hungary. |
|Aug 9||Montenegro declares war on Germany. |
The Togoland Campaign begins.
|Aug 7-Aug 10||Battle of Mulhouse, a phase of the Battle of the Frontiers. |
|Aug 7-Sept 13||Battle of the Frontiers. The Germans obtain a victory against the British Expeditionary Force and France's Fifth Army. |
|Aug 7||The British Expeditionary Force arrives in France. Details|
|Aug 6||Austria-Hungary declares war on Russia. |
Serbia declares war on Germany.
|Aug 5||Montenegro declares war on Austria-Hungary. |
The Ottoman Empire closes the Dardanelles.
|Aug 4–16||The Germans besiege and then capture the fortresses of Liège, Belgium. Details|
|Aug 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
The United States declares neutrality.
|Aug 3||Germany declares war on France. Belgium does not allow German arms through to the French border. |
|Aug 2-26||Germany sieges and captures fortified Longwy "the iron gate to Paris" near the Luxembourg border, opening France to mass German invasion |
|Aug 2||Germany invades Luxembourg. Details|
Skirmish at Joncherey, first military action on the Western Front
|Aug 1||Germany declares war on Russia. |
Italy declares its neutrality.
Germany and the Ottoman Empire sign a secret alliance treaty. Details
|July 31||Germany warns Russia to stop mobilizing. Russia says mobilization is against Austria-Hungary only. |
|July 28||Austria-Hungary declares war on Serbia. Russia mobilizes. |
|July 23||Austria-Hungary sends an ultimatum to Serbia. The Serbian response is seen as unsatisfactory. Details|
|July 5||Austria-Hungary seeks German support for a war against Serbia in case of Russian reaction. Germany gives assurances of support. |
|June 28||Assassination of Austro-Hungarian Empire Heir Archduke Francis Ferdinand and his wife heightens existing tensions between Austro-Hungary and Serbian protector Russia. Details|
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