Prussia has gone to war. On the evening of the 13th the Emperor seized the Landgrafenberg above Jena; through the night Lannes's corps and the Guard were crammed onto its narrow summit, and guns were hauled up the Steiger by torchlight.
On the plateau to the west, Prince Hohenlohe's 38,000 Prussians and Saxons believe they face only a flank guard. Rüchel's 15,000 are at Weimar; the King and Brunswick are marching north with the main army. At dawn the plateau lies under thick fog.