원문 - 영어 - The German siege of Verdun and its ring of forts,...

The German siege of Verdun and its ring of forts, which comprised the longest battle of the First World War, has its roots in a letter sent by the German Chief of Staff, Erich von Falkenhayn, to the Kaiser, Wilhelm II, on Christmas Day 1915.

In his letter to the Kaiser, Falkenhayn argued that the key to winning the war lay not on the Eastern Front, against Russia – whom he believed was on the point of revolution and subsequent withdrawal from the war – but on the Western Front.