November 20, 1917 - British forces open the Battle of Cambrai. With the failure of the offensives against Passchendaele, British Commander-in-Chief Field Marshal Sir Douglas Haig approved an attack against Cambrai. Featuring the first large-scale tank assault in history, the attack began on November 20 and saw British forces make swift gains. Increasingly bogged down by arriving German reserves, the offensive ground to a halt on November 28. Two days later, the Germans launched a massive counterattack using new "stormtrooper" tactics which threw back the British. By the end of the campaign on December 6, the front had returned to the pre-battle status-quo.
World War I - 1917:
Photograph Source: Public Domain