On War

by Carl von Clausewitz

When the Prussian army was, in October, 1806, waiting in Thuringia for the French under Buonaparte, the former was posted between the two great roads on which the latter might be expected to advance, that is, the road to Berlin by Erfurth, and that by Hof and Leipsic. The first intention of breaking into Franconia straight through the Thuringian Forest, and afterwards, when that plan was abandoned, the uncertainty as to which of the roads the French would choose for their advance, caused this intermediate position. As such, it must therefore have led to the adoption of the measure we have been discussing, a hasty interception of the enemy in front by a lateral movement.

This was in fact the idea in case the enemy marched by Erfurth, for the roads in that direction were good; on the other hand, the idea of a movement of this description on the road by Hof could not be entertained, partly because the army was two or three marches away from that road, partly because the deep valley of the Saale interposed; neither did this plan ever enter into the views of the Duke of Brunswick, so that there was no kind of preparation made for carrying it into effect, but it was always contemplated by Prince Hohenlohe, that is, by Colonel Massenbach, who exerted all his influence to draw the Duke into this plan. Still less could the idea be entertained of leaving the position which had been taken on the left bank of the Saale to try an offensive battle against Buonaparte on his advance, that is, to such an attack in flank as we have been considering; for if the Saale was an obstacle to intercepting the enemy in the last moment (à fortiori) it would be a still greater obstacle to assuming the offensive at a moment when the enemy would be in possession of the opposite side of the river, at least partially. The Duke, therefore, determined to wait behind the Saale to see what would happen, that is to say, if we can call anything a determination which emanated from this many-headed Headquarters’ Staff, and in this time of confusion and utter indecision.

Whatever may have been the true condition of affairs during this state of expectation, the consequent situation of the army was this:—

1. That the enemy might be attacked if he crossed the Saale to attack the Prussian army.

2. That if he did not march against that army, operations might be commenced against his communications.

3. If it should be found practicable and advisable, he might be intercepted near Leipsic by a rapid flank march.

In the first case, the Prussian army possessed a great strategic and tactical advantage in the deep valley of the Saale. In the second, the strategic advantage was just as great, for the enemy had only a very narrow base between our position and the neutral territory of Bohemia, whilst ours was extremely broad; even in the third case, our army, covered by the Saale, was still by no means in a disadvantageous situation. All these three measures, in spite of the confusion and want of any clear perception at head-quarters, were really discussed; but certainly we cannot wonder that, although a right idea may have been entertained, it should have entirely failed in the execution by the complete want of resolution and the confusion generally prevailing.

In the two first cases, the position on the left bank of the Saale is to be regarded as a real flank position, and it had undoubtedly as such very great qualities; but in truth, against a very superior enemy, against a Buonaparte, a flank position with an army that is not very sure about what it is doing, is a very bold measure.

After long hesitation, the Duke on the 13th adopted the last of the plans proposed, but it was too late, Buonaparte had already commenced to pass the Saale, and the battles of Jena and Auerstadt were inevitable. The Duke, through his indecision, had set himself between two stools; he quitted his first position too late to push his army in before the enemy, and too soon for a battle suited to the object. Nevertheless, the natural strength of this position proved itself so far that the Duke was able to destroy the right wing of the enemy’s army at Auerstadt, whilst Prince Hohenlohe, by a bloody retreat, was still able to back out of the scrape; but at Auerstadt they did not venture to realise the victory, which was quite certain; and at Jena they thought they might reckon upon one which was quite impossible.

In any case, Buonaparte felt the strategic importance of the position on the Saale so much, that he did not venture to pass it by, but determined on a passage of the Saale in sight of the enemy.