Final answer:
The event leading to the German surrender in World War I was the armistice on November 11, 1918, which followed Allied victories and internal unrest in Germany.
Step-by-step explanation:
The event that ultimately led to the surrender of Germany in World War I was the armistice on November 11, 1918. This armistice was a result of the Allied forces gaining significant victories in the latter part of 1918, and Germany facing internal unrest and military pressure.
In 1918, Russia had already surrendered and signed a peace treaty with Germany, which allowed the German forces to concentrate on the Western front. However, the arrival of mass numbers of U.S. troops in Europe bolstered the Allied forces and pushed Germany to the brink of collapse.
With civil unrest in Berlin and loss of support from the military high command, German Emperor Kaiser Wilhelm II abdicated his throne on November 9, 1918. Two days later, Germany and the Allies declared an immediate armistice, bringing an end to the fighting and signaling the beginning of peace negotiations.
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