Hindenburg Line
On 29th August, 1916, Paul von Hindenburg became Chief of Staff of the German Army. Hindenburg and his quartermaster general, Erich von Ludendorff, decided to build a system of German defence fortifications behind the northern and central sectors of the Western Front. Constructed between the northern coast and Verdun, each sector had its own system of mutually supporting strongpoints backed up with barbed wire, trenchworks and firepower.
After the failure of the Spring Offensive the German Army retreated to the Hindenburg Line. It was not until 5th October, 1918, that the Allied forces were able to gain complete control of these defences. When this happened, the Third Supreme Command realised that Germany was beaten and handed over power to Max von Baden and the Reichstag.
Primary Sources
(1) Philip Gibbs was a journalist who reported the war on the Western Front.
We thought these tanks were going to win the war, and certainly they helped to do so, but there were too few of them, and the secret was let out before they were produced in large numbers. Nor were they so invulnerable as we had believed. A direct hit from a field gun would knock them out, and in our battle for Cambrai in November of 1917 I saw many of them destroyed and burnt out.
But after the German retreat from the Somme battlefields it was the tanks who broke the Hindenburg Line, which the enemy had believed impregnable. They had dug a wide anti-tank ditch too broad for any tank to cross. But the commander of tanks, General Hugh Elles, had thought that out. He ordered the gathering of vast quantities of twigs and small branches of trees. They were tied into bundles like the Italian fasces. He called them fascines. Each tank advanced upon the Hindenburg Line with one of those bundles on its nose. By working a pulley the skipper could drop it into the ditch, then by nosing forward he could get the front part of the tank on to the bundle and so reach across.