Men drowned in shell craters filled with liquid mud. Four months of fighting for 5 miles of Belgian swamp — then Allied forces abandoned it all the following spring.
The Third Battle of Ypres, known as Passchendaele, began July 31, 1917, in the worst terrain of the war. The Flemish lowlands depend on drainage ditches to stay habitable. Months of artillery fire had destroyed the drainage. Summer rains arrived on schedule. The battlefield turned into a lake of liquid mud dotted with shell craters — each one a death trap for any man who fell in.
Men and horses drowned in the mud. Wounded soldiers who slipped off the narrow duckboard walkways could sometimes not be rescued — the mud simply swallowed them. One soldier described watching a man sink slowly while others stood helpless, unable to reach him without sinking themselves. The mud was everywhere, in everything, relentlessly and always.
Field Marshal Haig had convinced himself that a breakthrough at Ypres could reach the Belgian coast and capture the German submarine ports at Bruges and Zeebrugge. His generals had doubts. General Hubert Gough, commanding the attack, later said he had warned that the ground was impassable. The offensive continued for four months regardless.
The Canadians arrived in October to finish what British and Australian troops had started. On November 6, 1917, after a series of grinding limited attacks, Canadian soldiers captured what remained of Passchendaele village — mostly rubble in a sea of craters. The four-month campaign had advanced the Allied line roughly 5 miles.
Total casualties reached an estimated 500,000 on both sides — about 275,000 Allied and 220,000 German. British Prime Minister David Lloyd George, who had tried repeatedly to halt the offensive, later wrote that Haig had turned the battlefield into 'a sea of mud in which thousands of our men drowned.' The civil-military tension would define British politics for years.
The cruelest postscript: the following spring, Germany's Spring Offensive swept forward, and British commanders ordered a retreat from the Passchendaele salient. Every inch captured at such terrible cost was voluntarily abandoned. The village of Passchendaele, which had cost hundreds of thousands of casualties to take, was given up in a single day.