France

The 1917 Battle of Passchendaele, also known as the Third Battle of Ypres or simply Third Ypres, was one of the major battles of World War I, in which British, ANZAC, Canadian and South African units engaged the Imperial German Army. The battle was fought for control of the village of Passchendaele (Passendale in modern Dutch, now part of the community of Zonnebeke) near the town of Ypres (Ieper in Dutch) in West Flanders, Belgium. The plan was to drive a hole in the German lines, advance to the Belgian coast and capture the German submarine bases there. It was intended to create a decisive corridor in a crucial area of the front, and to take pressure off the French forces. After the Nivelle Offensive the French Army was suffering from extremely low morale, resulting in mutinies and misconduct on a scale that threatened the field-worthiness of entire divisions.

Although the period of the battle saw spells of good weather lasting long enough to dry out the land, Passchendaele has become synonymous with the misery of fighting in thick mud. Most of the battle took place on largely reclaimed marshland, swampy even without rain. The extremely heavy preparatory bombardment by the British tore up the surface of the land, and heavy rain from August onwards produced an impassable terrain of deep "liquid mud", in which an unknown number of soldiers drowned. Even the newly-developed tanks bogged down.

The Germans were well-entrenched, with mutually-supporting pillboxes which the initial bombardment had not destroyed. After three months of fierce fighting the Canadian Corps took Passchendaele on 6 November 1917, ending the battle, but in the meantime the Allied Powers had sustained almost half a million casualties and the Germans just over a quarter of a million. The Allies had captured a mere five miles of new front at a cost of 140,000 lives, a ratio of roughly 2 dead soldiers per inch gained.

Compounding this staggeringly Pyrrhic figure was the fact that the area was not even considered particularly valuable from a strategic standpoint; in March 1918--a mere 4 months later--the Allies abandoned to the Germans every inch of territory gained at such cost at Passchendaele in order to free several divisions to cover more strategically valuable terrain during the German Lys Offensive towards Ypres.