As part of the Visual Timeline series
1914:


(Jun 28th) Austrian archduke Franz Ferdinand assassinated in Sarajevo, Serbia (by Serbian nationalist Gavrilo Princip)

(Jul 28th) Austria-Hungary declares war on Serbia, officially starting WW1
(Jul 31st) Russia mobilizes to aid Serbia
(Aug 1st) Germany mobilizes to aid Austria-Hungary
(Aug 3rd) France declares war
(Aug 4th) Germany invades Belgium, fastest route to quickly capturing Paris; Britain declares war
(Aug 12th) British expeditionary force lands in France
(Aug 15-24th) Serbia repels Austria-Hungarian invasion at Battle of Cer
(Aug 28th) British win first naval battle, Battle of Heligoland Bight, sinking 3 German cruisers and impose naval blockade on Germany
(Aug 24-30) Germany repels Russian offensive into east Prussia at Battle of Tannenberg

(Aug) Britain-France and Germany war in African colonies
(Sep 5th) First submarine warfare, Germans sink British cruiser
(Sep 5-12th) France repels German offensive on Paris at First Battle of the Marne. Germany and Allies try to outflank each other until they reach North Sea. (*Parisian taxi drivers move 5 battalions (4k men) to front line)
(Sep 7-14th) Germans push Russians further back, Battle of Masurian Lakes
(Aug-Sep) German colonies in Pacific surrender to Australia-New Zealand forces
(Oct) Allies repel Germans at Battle of Ypres, Belgium

(Oct 29th) Ottoman empire joins Central Powers to fight against Russia
(Nov) Germans attack Warsaw, Battle of Lodz
(Nov 7th) Japan (allied with Britain France Russia) capture German naval base in Tsingtao, China
(Nov 23rd) British capture Ottoman port of Basra, securing access to vital Persian oil
(Nov-Dec) Germany and Britain naval battles in Southern Cone
(Dec 2nd) Austria-Hungary captures Belgrade, but Serbs counter and push back again
(Dec 16th) Germans raid British coast
(Dec 20th) French launch first major offensive against Germany, small gains at big cost
(Dec 22nd) Ottoman offensive into Caucasus ends in disaster, Battle of Sarikamish
(Dec 25th) Xmas truce in Western front trenches

1915: Bad year for Allies
(Jan 19th) World’s first air bombing campaign: 2 German zeppelins bomb Britain
Germany imposes its own blockade on Britain with its U-boats
(Feb 7th) Germany defeats Russians at 2nd Battle of Masurian Lakes
(Feb) Ottomans repel British and French naval attack near Constantinople

(Mar 10th) British-Indian trench offensive repeled by German barbed wire and machine gun
(Mar 22nd) Russia captures Przemysl, Austria-Hungary after 4 month siege
(Apr 22nd) First chemical warfare; German chlorine gas in western front trenches

(25th Apr) Gallipoli landings by ANZAC

(Apr) First effective fighter aircraft Fokker Eindecker goes into German service
(Apr 1915-1916) Armenian Genocide by Ottomans; 600k dead
(May 2nd) Central Powers break through Russian defences, beginning steady advance against Russia
(May 7th) British passenger ship torpedoed, killing some Americans
(May 9th) Another British-French trench offensive with big casualties and small gains
(summer) German aircraft with mounted machine guns air superiority
(May 23rd) Italy joins Allies, tempted by Austro-Hungarian territory
(Jun 23rd) Italians start series of unsuccessful attacks on Austria-Hungary (in modern Slovenia), 12 Battles of Isonzo. Big casualties, minimal territorial gains, but diverts Central Power troops.
(Aug 5th) German troops occupy Warsaw
(Aug 6th) Allies land reinforcements near Gallipoli but unsuccessful in breaking deadlock
(Aug 19th) German U-boat sinks another passnger ship with some Americans, after American warnings Germany stops attacks on US passenger ships
(Sep 25th) Great Autumn Offensive by Allies on Western front, small gains, big losses on all sides

(Oct) Bulgaria joins Central Powers, Serbia overwhelmed

(Oct-Nov) More failed Italian offensives against Austria-Hungary (Battles of Isonzo)
(Nov 22nd) Ottomans repel British advance on Baghdad
(Dec 18th) Allies evacuate from Gallipoli
1916:
(Jun-Sep) Russian Brusilov Offensive pushes back Eastern front.
(Jan) Britain introduces conscription; (Feb) Britain begins tank production; (Apr 24-29) Easter Rising, Irish revolt against British rule in Dublin, suppressed;
(May 31st – Jun 1st) British defeat Germans at battle of Jutland, only major naval battle of war


(Jun) most successful figher aircraft of war, British Sopwith Camel goes into action; (5th Dec) British PM Asquith resigns, succeeded by by George
(Jan 6th) Austria-Hungary attacks Montenegro, surrenders 3 weeks later
(Feb21st – Dec18th) Costly German Western front offensives, Battle of Verdun, war of attrition
(Mar 18th) Russia Eastern front offensive fails
(May 15th) Austro-Hungary successful surprise attack on Italians at Asiago
(Jun4th-Sep20th) Russian Brusilov Offensive pushes back Eastern front
(Jul 1st) First day of major Allied offensive, Battle of Somme (Jul-Nov1916), ends in disaster

Romania joins Allies
(Aug 27th) Romania advance into Transylvania repelled
(Aug 29th) Germany calls off from Battle of Verdun
(Sep 12th) Bulgarian resistance repels Allied offensive into Central Power-occupied Serbia
(Sep 15th) British use tanks at Battle of Flers, Western trenches, but limited success
(Sep-Nov) Italians make repeated costly assaults at Isonzo
(Nov 18th) Battle of Somme ends, limited gains for mass casualties both sides, war of attrition
Romania overwhelmed by Central Powers

(21st Nov) Austrian emperor dies
(13th Dec) French general Joffre dismissed, replaced by Nevelle
(Dec 30th) Rasputin murdered
(Jan 9th) Russian offensive in Caucasus
(Feb) Britain victories over Germany in Africa
(Apr) British at Kut (Iraq) surrender to Ottomans after 5-month siege
(Apr 29th) British at Kut (Iraq) surrender after 5 month siege
(May 9th) Britain and France secretly sign Sykes-Picot agreement to carve up the Ottoman Empire into their respective spheres of influence.
(May 10th) Arabs capture Mecca after Allies convince the Arabs to revolt against the Ottomans in exchange for independence after the war.


1917:
(1st Feb) Germany resumes unrestricted submarine warfare, knowing they will lose war of attrition
(Feb-Aug) Unrestricted German U-boat attacks contribute to more nations joining Allies
(Apr) U-boat most successful month of war, sinking 900 kt (17 ships a day), Britain will starve soon


Russian troops begin to desert on Eastern front
(Mar 15th) Russian Tsar Nicholas II abdicates, provisional govt put in place
(Apr) Germany gets Lenin out of exile in Switzerland, and charters train to Russia to start revolution
(1st Jul) Russian eastern front offensive fails, morale falls, Central Power counterattack almost unopposed
(7th Nov) Bolshevik Revolution, Lenin determind to end Russia’s involvement in WW1
(Dec 3rd) Russia signs armistice with Germany
(Dec 6th) Finland declares independence from Russia, and undergoes civil war. German-backed conservative Whites defeat Communist Reds on May 1918.
(Dec 9th) Romania isolated by Russian collapse, signs armistice with Central Powers
(9th Apr) Allied push Western front further at Battle of Arras
(Apr) bloody April, German planes air superiority
(Apr 16th) Nivelle Offensive, big losses, French units mutiny. Nivelle replaced by general Pattan who promises no more suicidal attacks

(Jun 7th) British tunnel under German lines at Battle of Messines, largest man-made explosion to date

(Jun 27th) King Constantine of Greece abdicates, Greece joins Allies
(Jul 19th) German parliament passes Peace Resolution Reichstag, but German high command rejects
(Jul 31st – Nov 10th) British offensive in Belgium, muddy, called off after 3 months; Battle of Passchendaele

(Aug 18th) 11th Battle of Isonzo

(Oct 24th) Central Powers defeat Italians at Battle of Caporetto, almost collapsing Italian front; Italys most humiliating defeat
(Nov 13th) Clemenceau becomes France PM, advocating total war and total victory
(Nov 20th) First major tank battle in history, British push forward at Battle of Cambrai, but pushed back after German reinforcements

(Feb 24th) British defeat Ottomans at 2nd Battle of Kut (Iraq)
(Mar 11th) British capture Baghdad
(Mar-Apr) British march into Sinai but repelled by Ottomans
(Jul 6th) Arabs capture strategic Ottoman port of Aqaba (accompanied by Lawrence of Arabia)
(Oct 31st) British defeat Ottomans at Gaza
(Nov 2nd) Balfour Declaration by British PM rallies for Jewish support in exchange for independent Jewish state in Palestine, contradicting existing pledges to Arab leaders.

(Dec 11th) British occupy Jerusalem, ending 400 year Ottoman rule
(22nd Jul) Siam joins Allies
(14th Aug) China joins Allies
1918:
(Feb) Most Ottoman empire strength focused on crushing attempts by Georgia, Armenia and Azerbaijan to create their own nations as Russians withdraw
(Mar 3rd) Amidst a Civil War (1918-1922), Bolshevik Russia exits war. Signs Treaty of Brest-Litovsk with Central powers, giving up vast amounts of Eastern European territory.

(Mar 21st) German spring offensive, Western front, threatening to split British and French armies
(Apr) Allies hold German offensive. Allies have now won air superiority
(May 18th) Britain’s first strategic bombing campaign, Cologne
(May) German offensive into France halted as fresh American divisions enter line
(Jun 15th) Austro-Hungary offensive into Italy repelled
(Jun 23rd) Allied troops land in Murmansk, Russia, intervening in Russian Civil War on side of White/Anti-Bolshevik forces
(Mar-Jul) Germany’s gamble on final offensive on Western front fails
(Aug 8th) Allies push back Germans supported by tanks and aircraft, German troops begin to surrender, Battle of Amiens begins Hundred Days Offensive
(Sep 15th) Allied push back Bulgarians, Bulgaria signs armistice 2 weeks later
(Sep 26th) Allied Grand Offensive on western front, and break through Hindenberg line
(Oct 4th) Germany requests Armistice to US; US demands Germany withdraw from all positions and kaiser abdicates
(Oct 24th) Allies deliver final blow to Austro-Hungarians at Battle of Vittorio Veneto
(Sep-Oct) British defeat Ottomans at Battle of Megiddo 19th Sep, Allies capture Damascus 1st Oct, and Aleppo on 26th Oct
(Oct 30th) Ottoman empire signs armistice
(Nov 3rd) Austria-Hungary signs armistice
(Nov 4th) Germany navy ordered to make suicidal attack but mutinies
(Nov 9th) Kaiser Wilhelm II abdicates; Germany becomes republic
(Nov 11th) Germany signs armistice inside railway carriage at Compiegne at 11th hour of 11th day of 11th month
(Nov 14th) general Lettow-Vorbeck in German East Africa surrenders, undefeated while cut off for 4 years




1919:
(18th Jan) Paris Peace Conference: former German possessions in China (Shandong Concession) handed to Japan; Poland re-emerges after 100 years of foreign rule
Austria, Czechoslovakia, Yugoslavia, and enlarged Romania emerges from Austro-Hungarian empire
(28th Jun) Treaty of Versailles restricts German military size, demands war reparations, loses territory and colonies. US Senate rejects Treaty of Versailles

(30 Oct 1918 – 1 Nov 1922) Ottoman Empire is partitioned


Ultimate victor of WW1 is the US.
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