January
  • 1. Turkey declares its independence of suzerainty of European powers. Ivernia, Cunard liner, is sunk in Mediterranean.
  • 3. Germany announces resumption of unrestricted U-boat warfare
  • 9. German leaders decide to launch unrestricted U-boat warfare
  • 10. Allies state war objectives in response to Wilson's peace note of 18 December
February
  • 1. Germany resumes unrestricted U-boat warfare
  • 3. United States severs diplomatic relations with Germany. Count Von Bernstorff is handed his passports.
  • 5. British General Staff estimates that no more than 250,000 American soldiers could be in Europe even after a year
  • 7. California, Anchor liner, is sunk off Irish coast.
  • 13. Chief of British Imperial General Staff Sir William Roberston expresses grave doubts about American fighting capabilities
  • 13. Afric, White Star liner, sunk by submarine.
  • 17. British troops on the Ancre capture German positions.
  • 24. Great Britain releases Zimmermann Note to US.
  • 25. Laconia, Cunard liner, sunk off Irish coast.
  • 26. Wilson requests authority from Congress to arm US merchant ships.
  • 26. Kut-el-Amara recaptured from Turks by new British Mesopotamian expedition under command of Gen. Sir Stanley Maude.
  • 28. United States government makes public a communication from Germans to Mexico proposing an alliance, and offering as a reward the return of Mexico's lost territory in Texas, New Mexico and Arizona.
  • 28. Submarine campaign of Germans results in the sinking of 134 vessels.
March
  • 1. Zimmermann Note released to press by State Department; Armed Ship Bill passes House
  • 3. British advance on Bapaume. Mexico denies having received an offer from Germany suggesting an alliance.
  • 4. Senate adjourns without passing Armed Ship Bill; "Little group of willful men" successfully filibuster
  • 8. US Naval Act carried appropriation of $1 million for purchase of basic aeronautical patents by the Federal Government.
  • 10. Russian Czar suspends sittings of the Duma.
  • 11. Bagdad captured by British forces under Gen. Maude.
  • 12. Wilson announces arming of merchant ships by executive order
  • 14. China breaks with Germany.
  • 15. Culmination of "February Revolution"; Czar Nicholas II abdicates. Prince Lvoff heads new cabinet.
  • 17. Bapaume falls to British. Roye and Lassigny occupied by French.
  • 18. Peronne, Chaulnes, Nesle and Noyon evacuated by Germans, who retire on an 85-mile front. City of Memphis, Illinois, and Vigilancia, American ships, torpedoed.
  • 19. Alexander Ribot becomes French premier, succeeding Briand.
  • 20. Wilson's Cabinet votes unanimously for war
  • 21. Healdton, American ship, bound from Philadelphia to Rotterdam, sunk without warning; 21 men lost. 26-31. British advance on Cambrai.
  • 29. War College Division issues report: Calls for large force of between 500,000 and 1,000,000 -- and optimistically estimates that at least ten months would be required to ship a force of 500,000 to Europe once it was raised and trained, putting the earliest effects of US involvement in mid- to late-1918; openly plans to send US force overseas, but argues against offensives through Macedonia or Holland; repeats opposition to sending an untrained American army overseas; Wilson publicly calls for a national army to be "raised and maintained exclusively by selective draft." The NACA recommended preparation of 3-year programs for aircraft production to the Secretaries of War and the Navy.
April
  • 1. German submarine campaign exacts heaviest damage of war: 881,027 gross tons, 500,000 of which are British
  • 2. Wilson delivers war address to Congress at 8:32 pm
  • 1. Aztec, American armed ship, sunk in submarine zone.
  • 5. Missourian, American steamer, sunk in Mediterranean.
  • 6. United States declares war on Germany. The Aviation Section of the Signal Corps consisted of 35 pilots, 1,987 enlisted men, and 55 training airplanes. Navy Aviation and Marine Corps combined had 48 officer-pilots, 239 men, 54 airplanes, 1 airship, 3 balloons, and 1 air station.
  • 7. Cuba and Panama at war with Germany.
  • 8. Austria-Hungary breaks with United States.
  • 9. Germans retreat before British on long front.
  • 10. Sir William Robertson advocates to Haig the dispatch of immediate American expeditionary force "to get some Americans killed and so get the country to take a real interest in the war".
  • 9. Bolivia breaks with Germany.
  • 13. Bolivia severs relations with Germany
  • 13. Vimy, Givenchy, Bailleul and positions about Lens taken by Canadians.
  • 16. Lenin arrives in Russia
  • 20. Turkey breaks with United States.
  • 22. President Wilson suggests to the belligerents a peace without victory.
  • 31. Germany announces intention of sinking all vessels in war zone around British Isles.
May
  • 7. First aerial bombing of London by German bombers at night.
  • 9. Liberia breaks with Germany.
  • 11. Russian Council of Workmen's and Soldiers' Delegates demands peace conference.
  • 15. Gen. Petain succeeds Gen. Nivelle as Commander-in-Chief of French armies. Gen. Foch is appointed Chief of Staff.
  • 16. Bullecourt captured by British in the Arras battles.
  • 17. Honduras breaks with German.
  • 18. Conscription begins, with the Selective Service Act signed by President Wilson.
  • 19. Nicaragua breaks with Germany.
  • 20. First aircraft sinking of a submarine, the German U-36, in the North Sea by a British flying boat.
  • 22-26. Italians advance on the Carso.
  • 28. Pershing leaves New York harbor for France aboard Baltic
June
  • 2. Aviation Section became the Airplane Division of the Army Signal Corps, and Maj. B. D. Foulois was appointed officer-in-charge on July 23.
  • 4. Aircraft Production Board and the Joint Technical Board on Aircraft authorized the construction of five prototype models of 8- and the 12-cylinder Liberty motors. Engine designs had been worked out in a Washington hotel room by J. G. Vincent of Packard Motor Car Co. and E. J. Hall of the Hall-Scott Motor Car Co. during the previous week, applying current engineering practices to mass production techniques.
  • 5. Registration day for new draft army in United States.
  • 7. General Staff issues plan to ship American forces at a rate of 120,000 per month beginning in August; this rate of dispatch would not be realized until April 1918
  • 7. Messines-Wytschaete ridge in English hands.
  • 8. Gen. Pershing, Commander-in-Chief of American expeditionary force, arrives in England en route to France.
  • 14. Wilson, in his Flag Day Address, declares that the initial American Expeditionary Force will be followed by more soldiers as quickly as possible, and that these soldiers will not be held in the US for training
  • 15. Espionage Act
  • 18. Haiti breaks with Germany.
  • 26. First US troops (1st Division) arrive in France
July
  • 1. Russians begin offensive in Gallicia, Kerensky, Minister of War, leading in person.
  • 2. Pershing makes first request for a US army of 1,000,000
  • 3. American expeditionary force arrives in France.
  • 4. First 8-cylinder Liberty aircraft engine arrived in Washington, D.C., for test by the National Bureau of Standards. Design, manufacture, and assembly of this motor had required less than 6 weeks.
  • 6. Canadian House of Commons passes Compulsory Military Service Bill.
  • 11. Pershing suggests that figure of 1,000,000 is only initial size, and a total force of 3,000,000 should be the goal
  • 12. King Constantine of Greece abdicates in favor of his secondson, Alexander.
  • 16-23. Retreat of Russians on a front of 155 miles.
  • 20. Alexander Kerensky becomes Russian premier, succeeding Lvoff.
  • 20. Drawing of draft number for American conscript army begins.
  • 22. Siam at war with Germany and Austria.
  • 27. First British DH-4 arrived in United States and became model for the first combat aircraft produced in volume in the United States.
  • 31. Passchendaele offensive (Third Battle of Ypres) opens in Flanders
  • 31. Franco-British attack penetrates German lines on a 20-mile front.
August
  • 1. Pope Benedict XV makes plea for peace on a basis of no annexation, no indemnity.
  • 7. Liberia at war with Germany.
  • 8. Canadian Conscription Bill passes its third reading in Senate.
  • 14. China at war with Germany and Austria-Hungary.
  • 15. Canadian troops capture Hill 70, dominating Lens.
  • 17. Field Marshal Jan Christian Smuts, Chairman of a Sub-committee on Imperial Defence, submitted classic proposal for creation of an autonomous air force in the British military structure.
  • 19. Italians cross the Isonzo and take Austrian positions.
  • 20. 95th Aero Squadron organized at Kelly Field, Texas
  • 21. First airplane powered by Liberty engine successfully flown, the L. W. F. Engineering Co.'s "Model F" biplane.
  • 25. US Navy "NC" flying boat development was initiated by Chief Constructor of the Navy, D. W. Taylor, in a memo outlining general requirements of such an aircraft to combat the submarine menace and "to fly across the Atlantic to avoid difficulties of delivery, etc." Acting Secretary of the Navy, F. D. Roosevelt, authorized development of "NC" flying boats capable of flying the Atlantic. 12-cylinder Liberty motor passed a 50-hour test with power output of over 300 hp prior to being ordered into mass production.
  • 28. Pope Benedict's peace plea rejected by President Wilson.
September
  • 1. Pershing establishes his general headquarters at Chaumont
  • 3. Riga captured by Germans.
  • 3. Brig. Gen. W. L. Kenly appointed Chief of the Air Service, AEF, the first time control of Army air activities was placed under a single head.
  • 14. Paul Painleve becomes French premier, succeeding Ribot.
  • 16. Russia proclaimed a republic by Kerensky.
  • 20. Costa Rica breaks with Germany.
  • 21. Gen. Tasker H. Bliss named Chief of Staff of the United States Army.
  • 26. Zonnebeke, Polygon Wood and Tower Hamlets, east of Ypres, taken by British.
  • 29. Turkish Mesopotamian army, under Ahmed Bey, captured by British.
  • 30. 95th Aero Squadron departs Kelly Field, Texas for Mineola, New York
October
  • 3. War Revenue Act; graduated income tax authorized
  • 6. Peru and Uruguay break with Germany.
  • 9. Poelcapelle and other German positions captured in Franco- British attack.
  • 11. Brazil severs relations with Germany
  • 17. Antilles, American transport, westbound from France, sunk by submarine; 67 lost.
  • 18. British De Havilland DH-4 ordered into series production in the United States 6 months after U.S. entry into World War I. By the end of the war, about 4,500 had been built, and of the total of 1,216 American-built planes to reach the Western Front, all but three (two Le Peres and one experimental DH-9) were DH-4's.
  • 23. American troops in France fire their first shot in trench warfare.
  • 23. French advance northeast of Soissons.
  • 24. Austro-German breakthrough at Caporetto on Italian front
  • 25. Italians retreat across the Isonzo and evacuate the Bainsizza Plateau.
  • 26. Brazil at war with Germany.
  • 27. 95th Aero Squadron departs Mineola, New York on White Star Liner Adriatic at Hoboken, New Jersey for England
  • 29. First DH-4 completed, flown at Dayton, Ohio.
  • 31. Beersheba, in Palestine, occupied by British.
November
  • 1. Germans abandon position on Chemin des Dames.
  • 3. Americans in trenches suffer 20 casualties in German attacks.
  • 6. Passchendaele captured by Canadians.
  • 6. British Mesopotamian forces reach Tekrit, 100 miles northwest of Bagdad.
  • 7. The Russian Bolsheviks seize power in Russia, led by Lenin and Trotzsky, seize Potrograd and depose Kerensky. Allied Supreme War Council created at Rapollo, Italy.
  • 8. Gen. Diaz succeeds Gen. Cadorna as Commander-in-Chief of Italian armies.
  • 10. Lenin becomes Premier of Russia, succeeding Kerensky. The 95th Aero Squadron arrives Liverpool, England.
  • 12. The 95th Aero Squadron arrives at Southampton, England.
  • 13. The 95th Aero Squadron arrives at Lellavre, France.
  • 15. Georges Clemenceau becomes Premier of France, succeeding Painlove. The 95th Aero Squadron arrives at Issoudun, France.
  • 20. British launch surprise tank attack at Cambrai.
  • 21. Ribecourt, Flesquieres, Havrincourt, Marcoing and other German positions captured by British.
  • 23. Italians repulse Germans on the whole front from the Asiago Plateau to the Brenta River.
  • 24. Cambrai menaced by British, who approach within three miles, capturing Bourlon Wood.
December
  • 1. German East Africa reported completely conquered. Allies' Supreme War Council, representing the United States, France, Great Britain and Italy, holds first meeting at Versailles.
  • 3. Russian Bolsheviki arrange armistice with Germans.
  • 5. British retire from Bourlon Wood, Graincourt and other positions west of Cambrai.
  • 7. Finland declares independence.
  • 7. United States and Austria-Hungary at war.
  • 8. Jerusalem, held by the Turks for 673 years, surrenders to British, under Gen. Allenby.
  • 9. Jerusalem captured by British
  • 10. Panama at war with Austria-Hungary.
  • 11. United States at war with Austria-Hungary.
  • 15. Armistice signed between Germany and Russia at Brest-Litovsk.
  • 16. U.S. Navy airplane design placed under LCdr. W. Starling Burgess, Bureau of Construction and Repair.
  • 17. Coalition government of Sir Robert Borden is returned and considered confirmed in Canada.
  • 22. Central Powers and Soviets open peace negotiations at Brest-Litovsk.