Aisne River in the context of "Hindenburg line"

The Hindenburg Line (Siegfriedstellung, Siegfried Position) was a German defensive fortification built during the winter of 1916–1917 on the Western Front in France during the First World War. The line ran from Arras to Laffaux, near Soissons, on the Aisne. In 1916, the Battle of Verdun and the Battle of the Somme left the German western armies (Westheer) exhausted and on the Eastern Front, the Brusilov offensive had inflicted huge losses on the Austro-Hungarian armies and forced the Germans to take over more of the front. The declaration of war by Romania had placed additional strain on the Imperial German Army and the war economy.

The Siegfriedstellung (Hindenburg Line) built behind the Noyon Salient, was to replace the old front line as a precaution against a resumption of the Battle of the Somme in 1917. By devastating the intervening ground, the Germans could delay an Anglo-French offensive. A shortened front could be held with fewer troops and with tactical dispersal, reverse-slope positions, defence in depth and camouflage, German infantry could be conserved. Unrestricted submarine warfare and strategic bombing would weaken the Anglo-French as the German armies in the west (Westheer) recuperated. On 25 January 1917, the Germans had 133 divisions on the Western Front but this was insufficient to contemplate an offensive.