German attack on Lagnicourt

The German attack on Lagnicourt (Unternehmen Sturmbock [Operation Battering Ram]) on 15 April 1917 was a military operation on the Western Front during the First World War. Four German divisions conducted a spoiling attack on the positions of the 1st Anzac Corps of the British Fifth Army. The attack was intended to delay the advance of the Fifth Army towards the Hindenburg Line, inflict casualties and destroy as much equipment, particularly artillery, as possible.

Sturmbock was also to deprive the British of the means to attack Gruppe Arras (IX Reserve Corps) as it fought the Battle of Arras (9 April to 16 May 1917) and Gruppe Quéant (XIV Reserve Corps) to the south. The German commanders hoped to gain time to prepare more defences and to show that the retirement to the Hindenburg Line had not diminished German morale or the ability to attack. The Fifth Army was recovering from the First attack on Bullecourt (11 April) and preparing for the Battle of Bullecourt (3–17 May 1917), a much bigger effort.

The attack by two divisions of Gruppe Quéant and two divisions of Gruppe Cambrai to its south, fell on the positions of the 1st Australian Division and the 2nd Australian Division. The Australians repulsed the attacks, except at Lagnicourt, where German troops broke in, took prisoners, destroyed six artillery pieces and captured confidential documents. Australian counter-attacks cut off some of the attackers and inflicted 2,313 casualties against 1,010 Australian.

The Fifth Army hurried forward more artillery and consolidated its defences, adding more advanced posts. Preparations for the next attack at Bullecourt continued and the Germans reinforced the Hindenburg Line (Siegfriedstellung) defences in the area. The attack was criticised by German commanders, especially for its rushed preparations, sparse results and severe casualties. The British moved no reserves from the 1st Anzac Corps area and continued the offensive at Arras.