People thought the war would be over quickly. Experts and leaders thought economies simply wouldn’t be able to keep up with the costs for long.
On the other hand, powers had been building up for a war like this for years, and new rail transport in Europe would accelerate mobilisations.
They had defence deals with others in case of attack. One was the Triple Alliance of Germany and Austria-Hungary and Italy, another the Triple Entente of France, the United Kingdom and Czarist Russia.
Austria-Hungary was junior to Germany in strength but both belligerents acted to bolster their prestige.
Britain backed France under a prior agreement to stop Germany changing the balance of continental power. Swiftly, the whole world became involved.
One key assassination — of the Austro-Hungarian heir to the throne the Archduke Franz Ferdinand — flung the armies into battle.
The prevailing mentality among war planners was to press massive attacks. Yet overwhelming strength was never enough. The lines bogged down in trench carnage for more than four years.
Sixty million soldiers fought. More than nine million of them were killed, and almost the same number of civilians. The wounded and disabled counted 20 million.
Then, Imperial Russia stopped fighting, leaving Germany free to concentrate on the western front. Then the Americans joined in.
Before the mighty intervention of the United States, however, the killing brought mass mutiny among the French. Mutiny also threatened among the Germans as their efforts neared collapse.
The German high command, renouncing the Kaiser (who fled into exile in the neutral Netherlands), sought an armistice.
A few photos recorded the signing in a railroad carriage at Compiègne, outside Paris. On that day, on “the eleventh hour of the eleventh day of the eleventh month” of 1918, a ceasefire came into effect.
The sides remained formally at war until the conclusive Treaty of Versailles of June 1919.
Although the armistice was celebrated, entire societies were warped and shocked. So many men were gone. Many returned to their home countries permanently damaged.
Whole nations, whether defeated or victorious, were less populated and poorer after the most ruinous war in history.
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