On the 15th April 1918, with the Germans, in the throes of a major spring offensive on the Western Front, hammering their positions in Flanders, France, British forces evacuate Passchendaele Ridge, won by the Allies at such a terrible cost just five months earlier, on April 15, 1918.
Under the command of Erich von Ludendorff, the German army launched “Operation Georgette,” the second phase of their first major offensive on the Western Front for more than a year, on April 9, 1918, near the River Lys in Flanders. In the first days of the attack, the Germans regained the momentum they had lost at the end of March, when the Allies halted the first phase of the attacks at Moreuil Wood and around Amiens, France. Storming ahead against the British and Portuguese divisions at the Lys (one Portuguese division was so overwhelmed it refused to go forward into the trenches after the initial bombardment), German forces advanced quickly as panic swept down the Allied lines of command.
On April 15, less than a week after Georgette began, the British were forced to evacuate Passchendaele Ridge, an area that had seen heavy bloodshed the previous fall, during the Third Battle of Ypres. That battle had ended in the Allied capture of Passchendaele on November 6, 1917, but only at the cost of 310,000 British casualties, compared with 260,000 on the German side. In addition to Passchendaele, the Germans gained control of Messines Ridge, the scene of another important Allied victory in June 1917, before the Allied defenses hardened and Ludendorff shut down the Georgette operation on April 29, 1918.