German withdrawal to the Hindenburg Line, 1917

Operation Alberich/Unternehmen Alberich
Part of World War I
New front line after Operation Alberich
Date 9 February – 20 March 1917 (withdrawal from 16–20 March). Location Picardy, France 49°30′N 02°50′E / 49.500°N 2.833°E / 49.500; 2.833Coordinates: 49°30′N 02°50′E / 49.500°N 2.833°E / 49.500; 2.833 Result German victory
Belligerents
British Empire  Australia  United Kingdom France	Germany
Commanders and leaders
Robert Nivelle Douglas Haig Hubert Gough Henry Rawlinson	Erich Ludendorff Crown Prince Rupprecht Fritz von Below

Unternehmen Alberich (Operation Alberich)
Part of Western Front 1914–1918
Type	Strategic withdrawal
Location	Noyon and Bapaume salients
Planned	1916–1917
Planned by	Generalfeldmarschall (Field Marshal) Kronprinz Rupprecht von Bayern
Commanded by	Erster Generalquartiermeister (Quartermaster-General) Erich Ludendorff
Objective	Retirement to the Siegfriedstellung (Hindenburg Line)
Date	9 February 1917 (1917-02-09) – 20 March 1917 (1917-03-20)
Executed by	Heeresgruppe Kronprinz Rupprecht von Bayern
Outcome	Success

 British Empire

Operation Alberich (Unternehmen Alberich) was the codename of a German military operation in France during World War I. It was a planned withdrawal to new positions on the shorter, more easily defended Hindenburg Line (Siegfriedstellung), which took place between 9 February and 20 March 1917 and eliminated the two salients which had been formed in 1916, between Arras and Saint-Quentin and from Saint-Quentin to Noyon, during the Battle of the Somme. The British referred to it as the German Retreat to the Hindenburg Line but the operation was a strategic withdrawal rather than a retreat under pressure.

Soon after taking over from Erich von Falkenhayn as Chief of the General Staff in at the end of August 1916, Paul von Hindenburg and Erich Ludendorff, the Erster Generalquartiermeister (First Quartermaster General) ordered the building of a new defensive line east of the Somme battlefront from Arras to Laon. Ludendorff was unsure as to whether retreating to the Siegfriedstellung (Hindenburg Line) was the best thing to do, since withdrawing might diminish the morale of German soldiers and civilians. An offensive was considered if enough reserves could be assembled in the New Year. A study suggested that seventeen divisions might be made available but that this was far too few to have decisive effect in the west. Ludendorff accepted the plan after representations by Rupprecht, Crown Prince of Bavaria, commander of Army Group Rupprecht (1st, 2nd, 6th and 7th armies, from the Somme front to the North Sea coast) over the objections of the 1st and 2nd Army commanders.

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