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From: Carl von Clausewitz and Arthur Wellesley, 1st Duke of Wellington. On Waterloo: Clausewitz, Wellington, and the Campaign of 1815. Ed./trans. Christopher Bassford, Daniel Moran, and Gregory W. Pedlow. Clausewitz.com, 2010. ISBN-10: 1453701508. ISBN-13: 9781453701508. 318pp. List price: $18.00.
STRATEGIC OVERVIEW OF THE CAMPAIGN
by Carl von Clausewitz
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Opposing Forces and Order of Battle
The order of battle and disposition of the main French army at the beginning of June were as follows:
|1st Corps (d’Erlon) at Lille||22,000|
|2nd Corps (Reille) at Valenciennes||24,000|
|3rd Corps (Vandamme) at Mezières||17,000|
|4th Corps (Gérard) at Thionville||16,000|
|6th Corps (Lobau) at Laon||14,000|
|The Guard (Mortier) at Paris||21,000|
|The four corps of reserve cavalry||15,000|
The Allied forces opposing this main French army were deployed as follows:
|2nd Corps under General Hill, which however stood on the right wing, consisted of:|
|Clinton's English Division||6,800|
|Colville's English Division||6,700|
|Prince Frederick of the Netherlands:|
|a) Anthing’s Dutch Brigade||3,700|
|b) Stedman’s Dutch Division||6,600|
|1st Corps, under the Prince of Orange, or the left wing from Ath to Nivelles:|
|Cooke's English Division||4,100|
|Alten's English Division||6,700|
|Perponcher’s 2nd Dutch Division||8,000|
|Chassée’s 1st Dutch Division||6,900|
|Collaert's Division of Dutch Cavalry||3,700|
|The Reserve under the direct command of the Duke of Wellington|
|Picton's English Division||7,000|
|Lambert's English Brigade and a Brigade of Hanoverian Landwehr||4,800|
|The Hanoverian Landwehr Division under General Decken||9,300|
|The Duke of Brunswick's corps at Mechelen||6,800|
|Nassau troops at Brussels||2,900|
The reserve cavalry under Lord Uxbridge, from Ghent via
Ninove to Mons
|Total [of Wellington's army]||93,800|
|2. Prussian army under Blücher|
|1st Corps, General Ziethen, at Charleroi||27,000|
|2nd Corps, General Pirch, at Namur||29,000|
|3rd Corps, General Thielmann at Ciney||24,000|
|4th Corps, General Bülow at Liége||35,000|
|Total [of Blücher’s army]||115,000|
3. Germanic Confederation troops from Northern Germany under
Reflections on Wellington's Dispositions:
Assumptions That Must Be Made
In order to draw any clear and instructive conclusions from the dispositions of the forces detailed above, we must have far more information than we presently possess. None of the previous historical writers who have written about this campaign have found it necessary to search for this data, and all that we have regarding the actual strategic relationships of the campaign, in terms of an exact representation of the situation prior to the two battles, is as fragmentary and scanty as for any old campaign of the 17th century.
The main points on which everything depends are:
1. An authentic and complete order of battle for Wellington's army, from which we can derive the disposition of the forces and the details of the chain of command. For example, in the order of battle above, the Hanoverian Landwehr Reserve under General Decken is counted as part of the main reserve. Yet it stood on the extreme right wing, took no part in the battle, and appears to have been used to garrison some fortresses, such as Antwerp, Ostend, and Ypres. Lyon's brigade, belonging to Colville's division, remained in Nieuport, did not come to the battle, and was probably also a garrison force. The 1st Corps under the Prince of Orange, which was supposed to have been the right wing, stood out of place on the left. Similarly, the divisions were out of order: for example, Perponcher and Chassée were reversed. As for Collaert's Dutch cavalry division, we do not know exactly what role was assigned to it prior to the 18th. In short, what we know about the order of battle of this army is so riddled with confusion that the numerous assumptions required for a strategic analysis of a campaign, which can normally be derived simply by examining the order of battle, are in this case either altogether absent, or confused and uncertain.
2. The defensive preparations and intentions of the Duke of Wellington. Whatever plans Blücher and Wellington had made to invade France are immaterial to us, since Bonaparte forestalled them by attacking first. But every force assembled for an attack remains in a state of defense until it advances to attack, and there must be a plan for this situation. However, we know nothing of the defensive plan for the Allied army in the Netherlands.
No such doubts exist with respect to the Prussian army. Two corps stood in the valley of the Meuse, where the cities of Liége, Huy, and Namur afforded quarters for large numbers of troops. A corps was on the Sambre around Charleroi, and another was on the right bank of the Meuse around Ciney, pushed forward like a pair of antennae. The headquarters was in the center at Namur, 13 to 18 miles from the advanced corps and connected with Brussels by a major road. The position extended 35 miles in breadth and depth. The force could be collected at its center in two days and could well expect to have two days in which to do so. Once the forces were concentrated, they could either give battle—if they considered themselves strong enough for that purpose—or retire in any direction. Nothing tied them to a particular spot or prevented them from acting as freely as possible.
All this was clearly not the case with the army of the Duke of Wellington. The army stretched from Mons to the sea, a distance of more than 90 miles; its depth was from Tournai to Antwerp, or about 65 miles. The headquarters at Brussels lay 45 miles from the front line of the cantonments. Such an army cannot concentrate on its center in fewer than four or five days. Yet the line of the French fortresses was much too close for anyone to be able to count on having four to five days to collect the army. The great fortress of Lille, for example, was only one day's march from Tournai.
But did the Duke of Wellington intend to concentrate his army at a single point? Was it sufficient simply to assemble the army, or did it have to concentrate at a particular point in order to protect something or enable him to act in concert with Blücher?
And if the intention of the Duke of Wellington was not to concentrate his forces at a single point but to defend with his forces more or less divided, then we must ask: What was the purpose of the individual positions and how did it all fit together?
We find not a single word about any of this. It is easy to suppose that the duke considered Brussels to be of special importance, but even if we were to accept this and consider Brussels as the only object to be protected, much depends on the degree of importance accorded it.
3. The base for Wellington's army, in particular its ultimate point of retreat or, alternatively, the freedom it had regarding[the choice of] this point, is an extremely important factor in determining what it could do.
4. Finally, what was available in the way of real fortresses, meaning places that might be left for a time to fend for themselves? The information we have speaks of places where defensive works had been undertaken but does not say to what extent these works had been completed, and still less how well they were equipped.
The duke no doubt had a clear understanding of all these matters, but we know nothing about them, and therefore cannot judge how well his view of the situation corresponded to the actual circumstances. If we can make conjectures based simply upon appearances rather than definite information, then the duke’s judgment must have been as follows: If Bonaparte attacks, he will advance against me and Blücher in several columns and on an extended front. It will therefore be necessary to take measures to ensure that Bonaparte encounters sufficient resistance everywhere while I keep a significant reserve that is ready to rush assistance to the point where the enemy’s main force may be found, and that is then capable of fighting a successful battle before this main force reaches Brussels. If the French push forward with their main force on their left wing, that is, in the vicinity of Lille, the reserve in Brussels would, by joining with Hill, be able to give battle somewhere on the river Dendre near Ath, with half or even three-quarters of the army participating, provided time and circumstances allow the [Allied] left wing to close up. If the main enemy force advances in the center, that is, from the vicinity of Maubeuge or Valenciennes, the reserve would unite with the Prince of Orange’s corps and, circumstances permitting, with a portion of Hill's corps in order to give battle on the road from Mons to Brussels. If the enemy advances with his main force on his right wing, that is, towards Charleroi or Namur, the reserve and perhaps a portion of the left wing could hasten to the assistance of the Prussians.
It is easy to see that a couple of days would be sufficient time for all of these plans, because all that was necessary was to combine the two corps of Hill and the Prince of Orange. Uniting with the Reserve at Brussels could then be accomplished simply by retreating one day's march toward Brussels. Given these assumptions, the duke’s preparations appear adequate, for he could scarcely fail to have a few days' [warning] time.
It was along these lines that the duke and Prince Blücher must have reached agreement in their meeting at [Tirlemont] in the beginning of May. Thus when considering the duke's promise to concentrate his army at Quatre-Bras and come to the assistance of Blücher in his chosen position at Sombreffe, if the main enemy force turned that way, it must be understood that the term "army" meant only the greater part thereof, that which Wellington himself may have called his main force—his reserve together with his left wing. It was completely impossible for Wellington's whole army, stretched out over ninety miles, to concentrate in two days on its extreme left, at Nivelles or Quatre-Bras. At most, the 6000-man left-wing division of Hill’s corps, namely Clinton's division, which was at Ath and Leuze, would be able to join in. The extended nature of Wellington's billeting area leads us to this assumption. Further confirmation seems to come from his decision to leave Prince Frederick of Orange near Hal, the fork in the road leading from Brussels to Lille and Valenciennes. These 19,000 men could certainly have reached the battle on the 18th. To this day there has been no explanation given for their being left behind, other than that they were to cover Brussels on that side.
If we now allow ourselves to consider these assumptions as historical facts and then submit them to critical analysis, it will be obvious that Bonaparte's way of operating and the circumstances of the moment have not been correctly understood. The whole expectation of a divided advance along a broad front is taken from other times, other commanders, and other situations. Bonaparte above all was one to gamble everything on the result of a single great battle. We say "gamble," not because this may be more risky than when the forces and their efforts are divided. On the contrary, circumstances may arise in which the latter course of action is a thousand times more hazardous than the former. We call it a gamble because, all rational calculation aside, the mind of man recoils from the idea of concentrating such an enormous decision into a single moment, as happens in a battle. It is as if our spirit feels confined in such a small space in time; we have the vague feeling that if we only had more time, we could find within ourselves a well of new resources. However, when these feelings are based not on objective circumstances but only on our emotions, this is merely the weakness of human nature. Strong-minded men will easily surmount such weakness, and in this respect Bonaparte must be reckoned among the strongest. Thus Bonaparte was first to venture everything in the tremendous act of a single battle. We must further state that he always preferred this kind of decision whenever circumstances permitted. However, seeking a decisive outcome through an all-encompassing battle can only come in circumstances where the overall goal is to reach a great victory. Furthermore, such a great victory can be the objective only:
1) if we know that our adversary seeks one and we cannot avoid it; [or]
2) if the impetus comes from us, and then only if we also have the means of carrying it through. One should only seek a great victory when one has the means of exploiting all its results, for a great victory and great danger stand side by side.
The latter was the case in all of Bonaparte's offensive wars; the former was the case now.
If Bonaparte never failed to seek an all-encompassing decision in the past, when he made war primarily to satisfy his thirst for fame and his lust for power, then surely nothing else could be expected of him now, when a modest success would be of no use and only an overwhelmingly complete victory, surpassing all his earlier ones, offered him any hope of a better future.
The most compelling assumption was therefore that Bonaparte would burst forth with his whole force against a single point.
Lord Wellington had never personally commanded against Bonaparte. Perhaps this is the reason why such an assumption did not impress itself upon Wellington as strongly as it would have on anyone who had ever been struck by the lightning bolt of one of Bonaparte's great battles.
If Lord Wellington had made this assumption, he would have carried out quite different arrangements for billeting his forces. As things actually were, it would have been impossible for him to appear with his entire force and operate together with Blücher, no matter what part of Belgium was chosen as the battlefield. But regardless of the assumptions made by Wellington, he could not have intended to leave a considerable portion of his forces out of the action.
Dispositions and Concentration of the Prussian Army
Let us now leave the intentions of Lord Wellington respecting his army in general, and his right wing in particular, in the obscurity from which they cannot be removed, because his original battle report makes not the slightest mention of this, and because no other writer has properly considered the subject. Let us instead concentrate on the results arising from the actual situation, that in the event that the enemy attacked Blücher, Lord Wellington would come to his assistance with his reserve, with his left wing, and perhaps with part of his right wing. Our goal will therefore be to examine this further, and also the concentration of Blücher's army.
We have already said that the Prussian army was placed so that it stretched 35 miles in breadth and depth and could be concentrated on Namur within two days. However, an exception must be made for the corps belonging to the North German Federal troops that stood at Trier. While this force was under Field Marshal Blücher’s command, it had been ordered to remain on the Moselle. This decision was no better than that for Wellington's right wing, but this was not the fault of Field Marshal Blücher, who did not count this corps as part of his army. As for his own force, we have already said that he had no plan other than to concentrate it once the enemy approached and then turn it in whichever direction the situation required. Against a commander like Bonaparte, and under the prevailing circumstances, this was absolutely the correct basis for all further decisions.
Object of the French Attack
In order to be clear in our own mind about what the Prussian army’s role would be after it had concentrated, we must ask ourselves what the objective of the enemy's strategic attack could be. Bonaparte's goal for this attack could only be a glorious victory over both Allied armies, as we have already said. If he inflicted a defeat on one or even both of them, such that Blücher was forced to retreat across the Rhine and Wellington into Zealand; if he took hundreds of cannon and many thousands of prisoners as trophies of victory; if he shattered the morale of both armies; if he shook the courage of both commanders and weakened their initiative; then he could hasten to the upper Rhine with a portion of his victorious army—even if it was only 50,000 men—and unite with General Rapp to form there a main army of 80,000 men. In a few weeks, this force would grow to 100,000 through reinforcements from the interior of the country. The terrible blow on the Lower Rhine would inevitably have produced delay and indecision [among the Allied forces] on the Upper Rhine, and the arrival of Bonaparte would have changed hesitation into fear for their own safety. A hasty retreat of all Allied forces located on the left bank of the Rhine, or their unexpected defeat, would have followed next.
Although the remaining force ratios would have left no reasonable basis for delaying the Allied attack upon France beyond the point when Russian reinforcements had arrived and Blücher and Wellington had recovered somewhat, it is very probable—when one looks at the lessons of similar cases—that the moral effect of the French victory could not have been overcome so quickly. Shaken and weakened by the effects of such a defeat, the Allies would have imagined a mass arming of the French populace and new French armies seemingly rising out of the ground. The two most distinguished leaders, Wellington and Blücher, would not have been on the scene, with the latter more than 450 miles from Allied Headquarters. It is thus possible that an excessive amount of time would have elapsed before the Allies felt themselves strong enough to take a step forward.
On the other side, would not such a victory have electrified France! In the heady triumph of this victory the vain, self-satisfied French would have laid their monarchism and their republicanism aside for the most part. The weapons would have fallen from the Vendéeans' hands, and Bonaparte's position inside France would have been completely different.
We are, however, far from accepting the general opinion that after such a victory, Bonaparte's situation would have become as favorable, firm, and unassailable as it had once been precarious. Such complete reversals are generally contrary to the nature of things and a very unworthy means of historical analysis. On the contrary, we think that Bonaparte's prospects would still have remained immensely difficult after even the most splendid victory and that such a victory would have given him only the barest possibility of resistance against the collective power of his enemies. The fact that he personally thought the most important immediate result of such a victory would be the fall of the British government in England and peace with that power only strengthens our impression of just how weak and uncertain he considered his position to be, because he wished to conceal this fact with such illusions.
A brilliant victory over the united armies in the Netherlands was therefore Bonaparte's most urgent requirement. This being the case, there could be only one objective for his endeavors, and this was the combined Allied army, not any geographical position such as Brussels or the right bank of the Meuse or even the Rhine, etc.
When a great, all-encompassing decision is at stake, geographical points and the connections of the army to them cannot be operational objectives in themselves, because the immediate advantages that such points give are too insignificant, and the more remote, long-term influence they may exert on the course of the war takes too long to have an effect. The great event of a battle would be like a mighty river sweeping away such a weak dike. Bonaparte's efforts could have been directed toward a geographical object only insofar as it would have afforded him a more advantageous prelude to the battle, particularly if it had given him the means of rendering the battle greater and more decisive, for this was his real need. Outflanking the enemy's army in order to attack it from a different direction, thus forcing it away from its natural line of retreat, is in most cases an unfailing means of intensifying a military action. But not always, particularly in the present case.
On the Prussian side, much has been said about the necessity of maintaining possession of the right bank of the Meuse, and Blücher's position on both banks of the river resulted from this. Similarly, Lord Wellington is considered to have attached great importance to covering Brussels. But what would have happened if Bonaparte had gained possession of the right bank of the Meuse or even of Brussels before the battle? The armies would have lost some unimportant supply columns and elements of their baggage trains, and perhaps also some stores of rations. Furthermore, in the former case the Prussian army, and in the latter the English, would have been pushed away from their natural lines of retreat. Clearly this would not have been particularly disadvantageous for either commander, because Blücher could easily unite with Wellington for a short time and retreat toward Mechelen and Antwerp, just as Wellington could unite with Blücher and turn towards the Meuse. The losses that both commanders would experience in case of a lost battle would not have been noticeably increased thereby, for there was no reason to fear either a long retreat or the possibility of encirclement.
It could thus be foreseen that Bonaparte would not place any value on such an outflanking maneuver. It would have cost him the far more valuable advantage of a quick and successful thrust and—if unsuccessful—could have placed him in great danger. We therefore believe that the two commanders could have united their forces at a single point and been certain that, no matter where this point lay, Bonaparte would seek it out. This union could not take place in advance because of the difficulties with provisioning, but the choice of a point of union was entirely up to them and not in any way dependent on the direction that Bonaparte himself chose.
The Point of Union of the Two Allied Armies
The most natural point for this union lay on the road from Brussels to Namur, where the two armies could join together most quickly. Blücher's headquarters had found that the area around Sombreffe—12 miles from Namur along this highway and barely 5 miles from the Brussels-Charleroi highway where Wellington intended to collect his left wing—was particularly well suited to serve as a battlefield against an enemy coming from the Sambre. The Ligny brook and one of its small tributaries, which run parallel to the highway between Sambre and Saint-Balâtre, carve out a strip of land that, while neither very deep nor very steep, is enough of both that the left side of the valley, which is higher, forms an excellent position for the employment of all arms. This position was of moderate extent (two or three miles), so that if occupied by one to two corps, it could be defended for a long time. In that case Blücher would still have two corps left for offensive operations, whereby he could win the battle either by himself or in conjunction with Wellington.
To be sure, the tactical characteristics of this position were only relevant against an enemy advancing from Charleroi. But since the strategic characteristics of this position completely met the requirements of all situations as well, the tactical advantages in this particular case played a role in the decision to select it.
If the two armies had united here in good time, either in a single position or in two sufficiently close that they could act in concert, they would have done everything their mission required, and could have left everything else to the decision of arms, which their great numerical superiority gave them no reason to fear. Whether Bonaparte’s line of march took him toward Brussels or anywhere else, he was obliged to seek out his opponents. But we have already said that Lord Wellington seems to have been far from considering such a concentration of forces and such a simplification of the problem of combining them. If he remained in his extended position even after the French army began to show signs of movement, then concentration at a single point was completely impossible. Even if it had been possible, he did not desire it. The thought of exposing Brussels even for a short time seemed inconceivable to him, and because the city was quite open, it could not be protected against incursions by a garrison alone. It is therefore certain that if Bonaparte had advanced on Brussels from Lille or Valenciennes, Lord Wellington would have hastened to oppose him, in the former case on the road from Tournai, in the latter on that from Mons. Then Blücher, in order not to remain idle, would also have had to go there. This he could have accomplished in about 36 hours, moving from Sombreffe to the road to Tournai. His forces would have been able to oppose the enemy in the vicinity of Enghien or at the worst near Hal. As Sombreffe lay exactly on this route, it was a perfectly good choice as a point of concentration in this respect as well.
On the other hand, Sombreffe would have been quite unsuitable for a defense on the right bank of the Meuse if the enemy were to advance along it. But how could Blücher have imagined he could collect his army on the right bank of the Meuse in time? And there could be even less thought of [receiving] any assistance there from the English commander. Blücher therefore understood better than Wellington the need to put aside whatever was not urgently required by the situation. He was certain of Wellington's support on the left bank of the Meuse, and if Bonaparte wanted to attack there, then he would have to cross the Meuse himself.
Calculation of the Time Required for Concentration:
The Prussian Army
Thus we see the Duke of Wellington uncertain about where to expect the enemy and prepared to oppose him everywhere with the greater part of his troops. We see Blücher resolved—as soon as the enemy bursts forward—to concentrate his army at Sombreffe, where he is near enough to the duke’s army to support it or be supported by it.
If we now look at the time both armies would require to concentrate, and compare it to the time that would have been available under the most unfavorable circumstances, based on the location of their forward corps, we find no satisfactory solution.
Charleroi is the closest place to the concentration point at Sombreffe and only about 12 miles away. If reports of the enemy's advance go from Charleroi to Namur, and then the order to assemble goes from there to Liège, the most distant billeting area, then we can calculate at least 16 hours for this process. If we then add the eight hours necessary for notifying and turning out the troops, 24 hours will have passed before the 4th Corps can begin its march. The route from the area around Liége to Sombreffe is 45 miles long, and for this distance even the fastest march requires two days. Consequently it would take a total of three days for this corps to arrive. The 3rd Corps in Ciney could be there in 36 hours; the 2nd Corps, from Namur itself, in 12 hours. General Ziethen’s resistance on the Sambre and his retreat to the vicinity of Fleurus could not gain more than one day of time; that is, he might delay the enemy from morning until evening, after which the arrival of darkness would supply the remaining time.
Naturally, one would not expect the enemy’s advance to be noticed only at the first cannon shot but at the very latest when he was in his final position prior to attacking our troops. Very probably this news would reach us a few days earlier by other channels. In that case there would be sufficient time to assemble the whole army. But if we were limited to what we could actually see, then only the 2nd and 3rd Corps could have arrived in time to receive 1st Corps at Sombreffe, and the 3rd Corps only with difficulty. [Bülow’s] 4th Corps could not have been there at all. This danger was fully appreciated at Blücher's headquarters, but there were all sorts of difficulties involved in moving Bülow's corps closer. Nevertheless, it received orders on the 14th—when the movements of the French army were noticed—to advance to the vicinity of Hannut, which is only 23 miles from the point of concentration. Consequently it might have reached there sooner than 3rd Corps, which was 30 miles away. As we will see later on, this did not happen because a chance event prevented this approach march from taking place immediately.
Blücher thus believed that he could collect his forces at Sombreffe in 36 hours. Although the chances were 100 to 1 that the enemy's advance would be known at least 36 hours before he reached the area of our battlefield, it was nonetheless very risky to remain in such an extended position when the enemy’s advance guard was so close. The continual difficulties that the Dutch authorities made with respect to provisioning prevented Marshal Blücher from collecting his forces to a greater extent, so he intended to wait for more definite reports on the movements of the enemy's army. He cannot, however, be entirely absolved from blame.
We can form no judgment about the assembly of Wellington's army, because we do not know the intentions and dispositions for the right wing. But this much is clear: For the scenario in which the least time would be available, that is to say, if the enemy advanced via Charleroi, the consequences for Wellington's army had to turn out even more unfavorably [than for Blücher’s]. In this case, even if no more than the left-wing division of the right-wing corps—namely, Clinton's—was to be brought over and the concentration was to take place at Quatre-Bras, this division had to march from Ath and Leuze, 37 and 47 miles respectively. This was the same distance that the news had to travel to reach Brussels, and the orders from Brussels to reach the corps. It is clear that this division would reach the battle even later than the Prussian 4th Corps. On the other hand, the left wing corps (whose furthest division was in Le Roeulx, 23 miles from Quatre-Bras), as well as the reserves around Brussels, could reasonably be expected to reach the battlefield within 36 hours. The fact that this did not occur resulted from circumstances we shall discuss later.
As long as it was known for sure that the French had one corps in the vicinity of Lille and another at Metz, there was no need to fear a sudden attack by concentrated forces. However, during the first days of June the French corps left Lille and Metz, and even though it was not known precisely what had occurred, the Allies received definite information around the middle of the month that the French 4th Corps had moved from the Moselle to the Meuse. From this moment onward, one could no longer count on having any additional warning before the outbreak of hostilities. It was now high time to draw closer together, and to do so in such a manner that all the corps could reach the field of battle within 24 hours. It is not necessary to describe all the changes in dispositions that would have been necessary, but it would have been very advantageous if the Duke of Wellington had placed his headquarters nearer to his corps and to that of Field Marshal Blücher, perhaps around Nivelles. This alone would have gained at least twelve hours and avoided much misfortune. But neither of these things took place. Only the Prussian 4th Corps received an order to concentrate in closer quarters near Hannut, and this order also came too late, as we shall see.
Part of the problem was the hope that more intelligence would be received before the outbreak of hostilities. Another part was Wellington’s belief that when he assembled his forces he must direct them toward the enemy's main force, about which there was no definite information as yet. No declaration of war had been made, and it was not yet known that the [Imperial] Guard had left Paris (which occurred on 8 June). Thus the Allies remained in a lamentable state of indecision until the 14th, in a situation where they clearly felt endangered, and from which they had decided to extract themselves, but in which they were nonetheless caught by surprise.
Bonaparte Assembles His Army
Bonaparte had decided to begin the campaign on 15 June. The 4th Corps departed Metz on the 6th. A few days later the 1st Corps left Lille. This movement was masked by strong pickets from the fortresses. On the 8th the Guard left Paris, the 6th Corps left Laon, and the 2nd Corps left Valenciennes. All these corps arrived between Philippeville and Avesnes on the 13th, the latter place being where Bonaparte himself also arrived that evening, having left Paris on the 12th.
From Metz to Philippeville is about 115 miles, which took the 4th Corps eight days. From Paris to Avesnes is 135 miles, for which the Guard needed only six days. The former distance, however, is over a lateral route without major roads. While it is impossible to judge a march without the fullest knowledge of all the details, we may safely assume that Bonaparte, whose main goal was to achieve surprise, had ordered his corps to proceed with the greatest possible speed. On the 14th the French corps drew even closer together, and took up the following positions in three columns:
The right wing, 16,000 men strong, consisting of the 4th Corps and some cavalry, around Philippeville.
The center, 64,000 men strong, consisting of the 5th and 6th Corps, the Guard and most of the cavalry, around Beaumont.
The left wing, 44,000 men strong, consisted of the 1st and 2nd Corps around Solre-sur-Sambre. This position was still 18 miles from Charleroi.
Since the move from Metz and Lille had not been merely a temporary concentration of the army's quarters but rather a genuine march of concentration, the Allies—if they had had a good intelligence system—should have found out about it before the 13th or especially the 14th—eight or nine days later; which would have dragged them out of their uncertainty earlier. But this did not happen. It was only on the 14th that they learned that the French were concentrating and that Bonaparte was with the army. It still remained uncertain just where this concentration would occur. It was not until the night of the 14th/15th that they learned through a report from General Ziethen that the enemy force facing him had been strengthened and that he expected an attack the next morning. Thus definite news was in fact received only 36 hours before the Battle of Ligny began.