Today the thing we find mysterious is why WWI lasted as long as it did. Why continue a pointless slaughter. Comparisions with the war in Ukraine suggest an answer!

My guess is is Professor David Stevenson and for him the mystery is not why it lasted so long but why it ended when it did.

For the German public is was particularly mysterious. Just a few months before the Armistice Germany was all conquering. Russia had been driven out of the war on terms hugely favourable to Germany. And in the West her storm troopers seemed poised to deliver victory on this front too.

And while the tide had clearly turned the German army was falling back in good order. So what compelled Germany to submit to allied terms? Was it a stab in the back as many Germany came to believe, or something else?

David is brilliant at unpicking all of this. As for the answer to the riddle - well, one place to look is in Bulgaria . . 

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