Well if you'd like to be pedantic the commonly accepted "end" to the Great War was 11 November 1918, or the day the armistice went into effect. The actual peace treaty would be signed in June of 1919, and fully put into effect the following year.
Also people commonly say that WW2 ended in 1945, even though the Paris Peace Treaties weren't signed until February 10 1947.
There are different types of victories in war, and different parts end at different times. I don't think a soldier sees a piece of paper as the end, if history tells us anything it's the start of the next war.