1915

Events

January

• January – British physicist Sir Joseph Larmor publishes his observations on "The Influence of Local Atmospheric Cooling on Astronomical Refraction".
• January 1
• * WWI: British Royal Navy battleship HMS Formidable is sunk off Lyme Regis, Dorset, England, by an Imperial German Navy U-boat, with the loss of 547 crew.
• *WWI: Battle of Broken Hill: A train ambush near Broken Hill, Australia, is carried out by two men who are killed, together with four civilians.
• January 5 – Joseph E. Carberry sets an altitude record of, carrying Capt. Benjamin Delahauf Foulois as a passenger, in a fixed-wing aircraft.
• January 12
• * The United States House of Representatives rejects a proposal to give women the right to vote.
• * A Fool There Was premières in the United States, starring Theda Bara as a femme fatale; she quickly becomes one of early cinema's most sensational stars.
• January 13 – 1915 Avezzano earthquake hits Italy, around 30,000 people are killed.
• January 17 – WWI: Caucasus Campaign – Battle of Sarikamish: Russia defeats Ottoman Turkey.
• January 18 – Twenty-One Demands from Japan to China are made.
• January 19
• * Georges Claude patents the neon discharge tube for use in advertising.
• * WWI: German Zeppelins bomb the coastal towns of Great Yarmouth and King's Lynn in England for the first time, killing more than 20.
• January 21 – Kiwanis is founded in Detroit, Michigan, as The Supreme Lodge Benevolent Order Brothers.
• January 23 – Chilembwe uprising: Baptist minister John Chilembwe initiates an ultimately unsuccessful uprising against British colonial rule in Nyasaland.
• January 24 – WWI: Battle of Dogger Bank – The British Grand Fleet defeats the German High Seas Fleet, sinking the armoured cruiser.
• January 25 – The first United States coast-to-coast long-distance telephone call is facilitated by a newly invented vacuum tube amplifier, ceremonially inaugurated by Alexander Graham Bell in New York City and his former assistant Thomas A. Watson, in San Francisco, California.
• January 26
• * WWI: The Ottoman Army begins the Raid on the Suez Canal.
• * The Rocky Mountain National Park is established by an act of the United States Congress.
• January 27 – WWI: French military casualties begin arriving at the Hôpital Temporaire d'Arc-en-Barrois, established earlier in the month by British volunteers.
• January 28 – An act of the United States Congress designates the United States Coast Guard, began in 1790, as a military branch.
• January 31 – WWI: Battle of Bolimów – Germany's first large-scale use of poison gas as a weapon occurs, when 18,000 artillery shells containing liquid xylyl bromide tear gas are fired on the Imperial Russian Army, on the Rawka River west of Warsaw; however, freezing temperatures prevent it being effective.

February

• February – While working as a cook at New York's Sloane Hospital for Women under an assumed name, "Typhoid Mary" infects 25 people, and is placed in quarantine for life on March 27.
• February 1 – William Fox creates the Fox Film Corporation.
• February 4 – The Maritz Rebellion of disaffected Boers against the government of the Union of South Africa ends with the surrender of the remaining rebels.
• February 8 – The controversial film The Birth of a Nation, directed by D. W. Griffith, premieres in Los Angeles. It will be the highest-grossing film for around 25 years.
• February 18 – WWI: Germany regards the waters around the British Isles to be a war zone from this date, as part of its U-boat Campaign.
• February 20 – In San Francisco, the Panama–Pacific International Exposition is opened.
• February 25 – Armenian genocide: The Ottoman Empire transfers Armenians from its armed forces to unarmed Ottoman labour battalions.

  March

• March – The 1915 Palestine locust infestation breaks out in Palestine; it continues until October.
• March 2 – Armenian genocide: Earliest recorded deportations.
• March 10–13 – WWI: Battle of Neuve Chapelle – In the first deliberately planned British offensive of the war, British Indian troops overrun German positions in France, but are unable to sustain the advance.
• March 11 – WWI: British armed merchantman is sunk in the North Channel off the coast of Scotland by Imperial German Navy U-boat SM U-27. Around 200 crew are lost, a number of bodies being washed up on the Isle of Man, with only 26 saved.
• March 14 – WWI:
• * Battle of Más a Tierra: Off the coast of Chile, the British Royal Navy forces the Imperial German Navy light cruiser SMS Dresden to scuttle.
• * Constantinople Agreement: Britain, France and the Russian Empire agree to give Constantinople and the Bosphorus to Russia in case of victory.
• March 18 – WWI:
• * Gallipoli campaign: A Franco-British naval attack on the Dardanelles fails.
• * British Royal Navy battleship sinks German submarine U-29 with all hands in the Pentland Firth off the coast of Scotland by ramming her, the only time this tactic is known to have been successfully used by a battleship.
• March 19 – Pluto is photographed for the first time, but is not recognised for what it is.
• March 26 – The Vancouver Millionaires win the Stanley Cup in ice hockey over the Ottawa Senators, 3 games to 0.
• March 28 – The first Roman Catholic liturgy at the newly consecrated Cathedral of Saint Paul, Minnesota, is celebrated by Archbishop John Ireland.

April

• April 5 – Boxer Jess Willard, the latest "Great White Hope", defeats Jack Johnson with a 26th-round knockout in sweltering heat, at Havana, Cuba. Willard becomes very popular among white Americans, for "bringing back the championship to the white race".
• April 11 – Charlie Chaplin's film The Tramp is released in the United States.
• April 21 – On the orders of Talat Pasha, Haydar Bey organized an expedition against the Assyrians. He killed thousands of Assyrians along with Kurdish tribes.
• April 22 – WWI: Start of Second Battle of Ypres – Germany makes its first large scale use of poison gas on the Western Front.
• April 24 – Armenian genocide: deportation of Armenian notables from Istanbul begins.
• April 25 – WWI: Start of the Gallipoli Campaign by land forces – A landing at Anzac Cove is conducted by Australian and New Zealand Army Corps, and a landing at Cape Helles by British and French troops, to begin the Allied invasion of the Gallipoli peninsula in the Ottoman Empire.

• April 26 – Treaty of London: Italy secretly agrees to leave the Triple Alliance with Germany and Austria-Hungary, and join with the Entente Powers, in exchange for certain territories of Austria-Hungary on its borders.

  May

• May 1 – General Louis Botha, Prime Minister of South Africa, leads the army in the occupation of German South West Africa.
• May 5 – WWI: Gallipoli Campaign – Forces of the Ottoman Empire begin shelling ANZAC Cove from a new position behind their lines.
• May 6 – Imperial Trans-Antarctic Expedition: SY Aurora's drift – The breaks loose from its anchorage during a gale, beginning a 312-day ordeal.
• May 7 – WWI
• * Sinking of the RMS Lusitania: 's main rival, the British ocean liner, is sunk by Imperial German Navy U-boat U-20 off the south-west coast of Ireland, killing 1,199 civilians en route from New York City to Liverpool. The best-known of the celebrities on board is American sportsman Alfred Gwynne Vanderbilt.
• * Germany captures the Latvian port city of Libau.
• May 9 – WWI – Second Battle of Artois: German and French forces fight to a standstill; German forces defeat the British at the Battle of Aubers Ridge.
• May 17 – The last purely Liberal government in the United Kingdom ends, when the prime minister H. H. Asquith forms an all-party coalition government, the Asquith coalition ministry, effective May 25.
• May 19 – WWI: The third attack on Anzac Cove by Ottoman forces is repelled by the Australian and New Zealand Army Corps.
• May 22
• * Quintinshill rail disaster in Scotland: The collision and fire kill 226, mostly troops, the largest number of fatalities in a rail accident in the United Kingdom.
• * Lassen Peak, one of the Cascade Volcanoes in California, erupts, sending an ash plume 30,000 feet in the air, and devastating the nearby area with pyroclastic flows and lahars. It is the only volcano to erupt in the contiguous United States this century, until the 1980 eruption of Mount St. Helens.
• May 23 – WWI: Italy joins the Allies after declaring war on Austria-Hungary.
• May 25 – China agrees to the Twenty-One Demands of the Japanese.
• May 27 – Armenian genocide: The Tehcir Law is promulgated by the Turkish Ottoman Empire authorizing deportation of the Ottoman Armenian population to Deir ez-Zor in the Syrian desert, leading to the deaths of anywhere between 800,000 and over 1,500,000 civilians and confiscation of their property.
• May 28 – International Congress of Women meets at the Hague as a major peace initiative.
• May 29 – Teófilo Braga becomes president of Portugal.

  June

• June – Armenian genocide: 15,000 civilians from the Ottoman Armenian population of Bitlis are massacred by Ottoman Turks and Kurds.
• June 3 – Mexican Revolution: Troops of Álvaro Obregón and Pancho Villa clash at León; Obregón loses his right arm in a grenade attack, but Villa is decisively defeated.
• June 5 – Women's suffrage in national elections is introduced in Denmark.
• June 9 – U.S. secretary of state William Jennings Bryan resigns over a disagreement regarding his nation's handling of the sinking of the RMS Lusitania.
• June 11 – Friar Leonard Melki and hundreds of other Christians are driven out of Mardin and massacred by Ottoman troops.
• June 16 – Women's Institutes are established in Britain.
• June 19 – In Iceland, at this time a dependency of Denmark, women's suffrage is granted to those over 40.