Timeline - 1910 - 1919

Airplanes are interesting toys, but of no military value.

Ferdinand Foch

1910

Ernest Rutherford proposed a model of the atom in which a very small, dense and positively charged nucleus of protons (the neutron had not yet been discovered) was surrounded by orbiting, negatively charged electrons (the Rutherford model).
6th May - HRH Edward VII died and was succeeded by HRH George V.
3rd October - In Portugal a group of republicans led by Machado Santos began a revolt that was be supported by several army units of the Lisbon garrison. The rebellion was be joined by a large segment of the population and by the sailors of the cruisers Sao Raphael and Adamastor.
4th October - Portugal became a republic, King Manuel II fled to England

1911

23rd October - The first aerial reconnaissance mission was flown by an Italian pilot over Turkish lines during the Italo-Turkish War

1912

The Republic of China was established, ending the Chinese Empire.
5th May - The Soviet Communist Party newspaper Pravda began publishing.

1913

Niels Bohr formulated the first cohesive model of the atomic nucleus, and in the process paved the way to quantum mechanics.
16th January - The British House of Commons accepted Home Rule for Ireland (but it was not put into effect due to the intervention of World War I).
4th March - Thomas Woodrow Wilson became President of the USA.
30th May - The Treaty of London was signed by the Great Powers, the Ottoman Empire and the victorious Balkan League (Serbia, Greece, Kingdom of Bulgaria, and Montenegro) bringing an end to the First Balkan War.
10th July - Romania declared war on Bulgaria
10th August - The 2nd Balkan War ended with the signing of the Treaty of Bucharest, Bulgaria lost.
27th October - President Thomas Woodrow Wilson said the US would never attack another country

1914

28th June - Gavrilo Princip assassinated Archduke Franz Ferdinand of Austria in Sarajevo, triggering the start of World War I.
4th August - Great Britain and France declared war on Germany.

1915

31st January - 1st (German) chemical warfare attack, against Russians. They used xylyl bromide tear gas (known as T-Stoff).
18th February - Germany began a blockade of Britain.
19th February -The Gallipoli Campaign began, also known as the Battle of Gallipoli or the Dardanelles Campaign was an unsuccessful attempt by the Allied Powers to control the sea route from Europe to Russia.
22nd February - Germany began "unrestricted" submarine war
22nd April - The first use of a lethal chemical warfare agent (chlorine) in the modern era by the German Army at the Second Battle of Ypres.
25th April - A major land invasion of the Gallipoli Peninsula, involving British and French troops as well as divisions of the Australian and New Zealand Army Corps (ANZAC).
7th May - A German U-Boat torpedoed the British passenger liner Lusitania off the Irish coast. She sank in 18 minutes, drowning 1,201 persons, including 128 Americans. President Woodrow Wilson subsequently sent four diplomatic protests to Germany.
3rd July - After exploding a bomb in US Senate reception room the previous day, Erich Muenter, a German instructor at Cornell University, shot J.P. Morgan for representing the British government in war contract negotiations
25th September - The Battle of Loos started, it lasted until 14th October. Chlorine gas deployed by the British was blown back into their own trenches causing 59,000 British & 26,000 German casualties.
11th October - Despite international protest, Edith Cavell, an English nurse in Belgium, was executed by the Germans on charges of aiding the escape of Allied prisoners
7th December - The British government authorized the evacuation from Gallipoli; the last troops left Helles on 9th January, 1916. In all, some 480,000 Allied forces took part in the Gallipoli Campaign, at a cost of more than 250,000 casualties, including some 46,000 dead. On the Turkish side, the campaign also cost an estimated 250,000 casualties, with 65,000 killed.
28th December - The British Cabinet recognised the true nature of the war by introducing military conscription, with single men to be called up before married ones

1916

8th January - ANZAC (Australian and New Zealand Army Corps) forces withdrew from the Gallipoli Peninsula after Ottoman forces successfully defended access to Constantinople.
21st February - The Battle of Verdun began with a German offensive, leading to an estimated 1 million casualties and became the longest battle of the entire war (9 months).
9th March - Germany declared war against Portugal.
1st July - First day of the Battle of the Somme - the British Army suffered its worst day, losing 19,240 men
7th October - The German submarine U-53 sank 9 British merchant ships in international waters off Newport, Rhode Island.
5th November - Emperors Wilhelm II (Germany) and Franz Jozef I (Austria-Hungary) established the Kingdom of Poland.
18th November - General Douglas Haig finally called off 1st Battle of the Somme - over 1 million had been killed or wounded
6th December - David Lloyd George (Liberal) became British Prime Minister.

1917

16th January - The "Zimmermann Telegram" was sent from Germany to Mexico, stating that in the event of the US entering World War I on the allied side, Mexico would be given Texas, Arizona and New Mexico. Intercepted by British intelligence and partially deciphered by the next day. It's release in March shifted US public opinion in favor of war against Germany.
3rd February - US liner Housatonic was sunk by German submarine, on the same day that US President Woodrow Wilson broke off diplomatic relations with Germany.
26th February - Russian February Revolution - Tsar Nicholas II ordered the army to quell civil unrest in Petrograd, the army mutinied.
April - Vladimir Lenin and other revolutionaries returned to Russia from Germany.
The Russian Civil War began.
6th April - The USA joined the Allies for the last 17 months of World War I.
5th June - 10 million US men began registering for the draft.
4th July - Troops of the Russian Provisional Government open fire on protesters in Petrograd during the 'July Days' of unrest
October - Revolution in Russia.

1918

27th January - Communists attempted to seize power in Finland.
28th January - Leon Trotsky became leader of the Russian Communists.
16th February - The Council of Lithuania declared the independence of the State of Lithuania.
20th February - The Soviet Red Army seized Kiev, the capital of the Ukraine.
3rd March - Germany and Austria forced Soviet Russia to sign the Peace of Brest, which called for the establishment of five independent countries - Estonia, Latvia, Lithuania, Poland and Ukraine. The Treaty of Brest-Litovsk, which ended Russian participation in World War I, was annulled by the November 1918 armistice. The treaty deprived the Soviets of White Russia.
5th March - The Soviets moved the capital of Russia from Petrograd to Moscow.
7th March - Finland signed an alliance treaty with Germany.
9th March - The Russian Bolshevik Party became the Communist Party.
23rd March - Germany became the first country to recognise the independence of Lithuania. This was based on the Lithuanian legislative act of Dec. 11, 1917.
25th March - Belarus declared independence.
17th July - The Russian Imperial Romanov family were assassinated,
30th August - Vladimir Lenin, the new leader of Soviet Russia, was shot by Feiga Haimovna Roytblat (aka Fanny Kaplan) and wounded after a speech.
14th October - The Czechoslovak National Council in Paris organized a provisional government of Czechoslovakia with T.G. Masaryk as president.
17th October - Yugoslavia proclaimed itself a republic.
18th October - Czechs seized Prague, renounced Hapsburg's rule and declared independence from the Austro-Hungarian Empire. T.G. Masaryk proclaimed the foundation of Czechoslovakia from Pittsburgh, Pa.
The independence of Poland was recognised by the UK.
28th October - The Czechoslovak National Congress in Prague proclaimed the independence of Czechoslovakia.
29th - 31st October - The Kingdom of Greater Serbia was proclaimed at Sarajevo in Bosnia bringing that state into what was later called Yugoslavia.
30th October - The Slovak National Council acceded to the November 28 Prague proclamation for the creation of the Czechoslovak state. Slovaks joined the Czechs to form Czechoslovakia.
3rd November - The Austro-Hungarian Empire was dissolved.
7th November - The Yugoslav National Conference at Geneva decided on the union of Croatia and Slovenia with Serbia and Montenegro.
11th November - At ten minutes past five in the morning, German and Allied negotiators placed the final signatures on the armistice that would end World War I six hours later. After the signing, French General Ferdinand Foch sent all Allied commanders the following message - "Hostilities will cease on the entire [Western] front November 11 at 11 - 00 a.m.". Even as the hour approached, 9 of 16 commanders of US divisions on the Western Front ordered a final assault that left an additional 11,000 casualties. The costs of the First World War were astronomical with 7.5 million dead and more than 35 million total casualties.
26th November - Montenegro deposed King Nicholas who opposed union, and voted to join the new Kingdom of Serbs, Croats and Slovenes.
1st December - The Kingdom of Serbs, Croats and Slovenes (later in 1929 to be called Yugoslavia) was proclaimed by Crown Prince Alexander Karadjordjevic.
USSR War with Poland started.

1919

5th January - The German Workers' Party formed, precursor to the National Socialist German Workers' Party (Nazi)
21st March - The Hungarian Soviet Republic was established by Béla Kun.
23rd March - 8th Congress of the Russian Communist Party re-established a five-member Politburo which became the centre of political power in the Soviet Union. The original members Vladimir Lenin, Leon Trotsky, Joseph Stalin, Lev Kamenev and Nikolai Krestinsky
28th June - The Treaty of Versailles, ending WWI and establishing the League of Nations, was signed in France.