Mapping the End of World War I.
Color-printed folding map showing the closing stages of World War I, after the Battle of Amiens when the Allies began securing many major victories.
In Spring 1918, the Germans launched a major offensive known as the Kaiserschlacht or Kaiser's Battle. The offensive began on the 21st of March and resulted in the deepest advances by either side since 1914. The Germans knew that their only hope of victory was to defeat the Allies before the full force of the United States came to bear on the Western Front, and after the Russian withdrawal from the war, they were able to redeploy forces from the East to attempt that feat. In the end, the Allies gave up huge amounts of largely worthless, battle-scarred territory to the Germans, who in turn could not keep their quickly-advancing units supplied. The German advance petered out by late April.
The failure of the German Spring Offensive to secure a quick victory meant that the United States could continue building up its forces on the Western Front. Beginning in July, a series of decisive Allied victories forced the Germans past the Hindenburg Line. These victories came to be known as the "Hundred Days Offensive". Once the Germans had retreated beyond the Hindenburg Line, they negotiated an armistice and the war ended.