Watched an old re-run of Pawn Stars where a customer took in a trophy/cup supposedly awarded for some sort of horse riding skill in WW1.A pop up box of facts that they sometimes show appeared which said WW1 was fought 1915 to 1919.To European eyes these dates of course don't tally,however from an American perspective it didn't start[officially at least]until 1915 after the sinking of the Lusitania[?] as for ending 1919 technically that is correct as although wars end is commemorated as November 1918 this is when the armistice came into force and the guns fell silent but the war didn't officially end until the peace was signed on June 21st 1919 up until which point the fighting could have re-started and the war continued.It was on this date that the crews of the High Seas Fleet scuttled all their vessels[including submarines]which they had sailed into Scapa Flow at the beginning of the armistice.
It is the difference between the "fought" and signing of The Versailles Treaty, which actually guaranteed, due to the way it was thrashed out and ridiculous, unfair to Germany, terms laid down, that another major European war at least would be fought in the near future. Maybe the American trophy used 1919 to cover the awful truth that their General John J. Pershing, commander of the American Expeditionary Force, wasted at least 3,500 American lives during the morning of 11th November, 1918, with the last man dying at 1058 that morning, even though it was known that the armistice had been signed at 0500, and would come into force at 1100. Like Haig, he failed to consider the worth of men's lives verses the actual gains that could be made by throwing troops into battle, with the feeble excuse that it was to keep the pressure up on the Germans, not let them give up on the armistice, and possibly (as some historians have stated) keep fighting them all the way back to Berlin!
However, it was not just Pershing who took such action. On the actual day of the Armistice the British and French generals did not know, or understand, that they could stop the terrible waste of life and continued to throw units into battle against the Germans, costing another 11,000 casualties, with 2,700 killed. In the main the Germans had had enough, and could not believe the Allies actions, with as much as they wanted to just stop using their guns, they found themselves under attack and had to react. Reports exist that German machine gun units stopped firing at 1100, then got up, saluted, and walked away from the front line.
The Americans being fresh to the war on April 6th, 1917, did so effectively as a result of the sinking of US shops. But it was mainly because a "German" map fell into the hands of the Yanks showing how Germany would name the various States after they joined Mexico and from there invaded the USA. It infuriated them. It is now recognised that in all probability the map / plan was a fake, manufactured by the British (very cleverly!
) to get the USA to join the war! Whether of not the Americans through combat "won the war" as they like to think is questionable, but certainly the effect on the Germans psychologically of hundreds of thousands of fresh combat American troops entering the fray was considerable and did give the advantage to the Allies, which they almost lost during the German Spring, or Ludendorff Offensive, with the Germans achieving the best gains of ground of the whole war. The American back-up did though finally make a difference and brought the terrible conflict to an end.