Four years earlier in 1914, 11 November had been the crucial day in the First Battle of Ypres when the Prussian Guards had made their supreme attempt to smash British resistance and breakthrough to Calais; Sir Douglas Haig's I Corps had held the line, the crisis had passed and with it Germany's chance of a swift 19th-century-style victory.
It was therefore fitting that 11 November 1918 should be the day that brought the whole tragic conflict to an end. From 9am on the 8th the Allied and German delegation had confronted each other across the table in a specially adapted restaurant car in Marshal Foch's command train parked on a track laid for railway guns in the Forest of Compiegne. Just after 5am on the 11th the instrument of armistice was signed. Instantly signals were despatched in all directions proclaiming a ceasefire for 11am.
It was also fitting that that morning the British took Mons (from which they had ingloriously retreated in the war's first weeks) and that the commander of the force that did so was General Sir Henry Horne, artillery chief of Haig's I Corps back in 1914. He wrote to his wife that evening: "I think we may well regard Nov. 11 1918 as a red-letter day."
In places the fighting continued well after 11 November. Elsewhere attacks were timed tight to the hour, so that one Canadian near Mons achieved the unenviable distinction of making the supreme sacrifice at 10.58.
Soldiers' reactions varied. An artillery sergeant told the news by his CO saluted, said "Very good, sir" and walked on. A company of Royal Engineers, fortified by a double dose of rum, lit flares, danced with civilians, and generally "mafficked" (i.e. rejoiced wildly as after the relief of Mafeking in the Boer War) until exhausted.
Some found celebration impossible. C.S. Lewis, then an infantry subaltern, bitter at the loss of friends he had trained with at Oxford in 1917, wrote: "The man who can give way to mafficking at such a time is more than indecent - he is mad. I remember five of us at Keble, and I am the only survivor. One cannot help wondering why. Let us be silent and thankful."
London was far from silent. As 11 o'clock struck the city erupted in what Churchill called "triumphant pandemonium". Huge crowds at Buckingham Palace brought the King and Queen on to the balcony, everybody in uniform saluting as bands played the national anthems of the victorious allies.
For Queen Mary writing that night in her diary this was "the greatest day in the world's history". In France a private soldier wrote in his: "Surely this is the last war that will ever be between civilised nations."
For the Kaiser, in Holland after his enforced abdication, this was the first full day of an exile that would last until his death in 1941. By then a second war would have begun, largely replaying the plot of the first. The prime architect of that later conflict had reacted bitterly to Germany's collapse in 1918. Hitler had heard the news in hospital after being temporarily blinded by gas. He would write in Mein Kampf: "So it had all been in vain . . . the death of two millions . . . Hatred grew in me . . . I resolved that, if I recovered my sight, I would enter politics."
Malcolm Brown is author of `The Imperial War Museum Book of 1918, Year of Victory' (Sidgwick & Jackson pounds 25)