The Battle of Passchendaele was an offensive launched by the Allies on 31st July 1917. It is also known as the Third Battle of Ypres. Passchendaele was the largest of the battles fought in and around the town of Ypres. It was a battle for control of a ridge that dominated views of the area. Victory here would ease pressure on the British troops in this sector. It had been a long term objective of the British that had been delayed by the need to focus on the Somme in 1916.
Context: Battle of Passchendaele
After the Battle of Arras the British High Command was eager to take up the offensive once again. The area around Ypres had been highly dangerous for troops throughout the war. The Ypres Salient was overlooked by Germans who held ground on several ridges. One of these, to the east of Ypres, was the Passchendaele ridge. Generals believed that after the success they had enjoyed at Arras they had the tools and tactics to succeed against the Germans. An assault against their positions at Passchendaele could be followed up by clearing the German army out of Belgium, freeing up ports for supplies and troops to get to the front from Britain with more ease. The belgian ports were also being used by German submarines to disrupt Allied shipping, if they were to be forced out of Belgium it would be very beneficial to the allied cause.
The tactic of bombardment had changed little. It was another massive bombardment. 3000 guns fired over 4.5 million shells in advance of the assault: though they were largely ineffective against well built positions. Much of the area in which the bombardment was taking place was relatively flat and the earth was clay based. The shelling left craters and as the ridge gave an elevated view, the Germans could see the preparations being made for the assault: very similar to the Somme, just that the gradient was lesser at this battle.
Assault on Passchendaele Ridge
On 31st July 1917 the assault began. The left flank of the assault reached its day one objectives. The right flank made no gains. Then the weather changed. The Ypres Salient was already known for its mud. Rain came down and soon the clay became very slippery and the craters began to fill with water. Moving men and machines around the battlefield was incredibly difficult in these circumstances. The assault continued though.
In Mid August the French had success at Langemark, the British had limited success elsewhere on the front. German counter attacks were frequent though. Those and the weather made gains hard to maintain. For a month the rain and mud led to a stalemate. Trenches were close in places. Conditions wet and dangerous. It was not until 20th September that a renewed assault could take place. Three attacks in short succession led to the capture of the ridge. Individually they are known as the Battle of the Menin Road, Battle of Polygon Wood and, on 4th October Battle of Broodseinde.
The ridge had been captured but no breakthrough achieved. The Belgian ports remained in German hands. However the 3 months of fighting had seen large numbers of casualties. Some 325,000 British casualties were recorded at the Battle of Passchendaele. The advantage gained was negligible but sufficient for High Command to claim victory and end the campaigning around Ypres in early November 1917.
Tactical Innovation at the Battle of Menin Road
One of the changes to tactics that led to the ridge being taken was the adoption of a strategy that became known as ‘bite and hold’. At the Battle if Menin Road the orders were quite simple. Advance 1500 yards into German lines but no further. Dig in. Artillery would then be retargeted and a second wave of troops would pass by the first, advancing another 1500 yards. In doing this, the officers had devised a method of making sure that the troops never advanced too far away from support. They were always able to make the most of the artillery at their disposal. The Allies also had air defence at this battle which was able to pass on information. Communications were leading to a much more coordinated and coherent attack. Additionally, with this tactic in place the front line troops were not exhausted. This made a large difference when facing Counter Attacks.
National Army Museum page on Passchendaele.
BBC history page on the Third battle of Ypres.