First Battle of Ypres

World War I battle of 19 October to 22 November 1914 on the Western Front around Ypres, Belgium, closing the Race to the Sea. French, British and Belgian troops in improvised field defenses repulsed repeated German attacks for four weeks; German reservist mass attacks at Langemarck suffered losses of up to 70 percent. The battle cemented the shift from maneuver warfare to the static, attritional trench warfare that defined the Western Front.