It will be remembered that Ney had been entrusted by Napoleon with the absolute and independent command of something less than half of his whole army.[7]
He had put at his disposal the First and the Second Army Corps, under Erlon and Reille respectively—nearly 46,000 men; and to these he had added, by an afterthought, eight regiments of heavy cavalry, commanded by Kellerman.
The rôle of this force, in Napoleon’s intention, was simply to advance up the Brussels road, brushing before it towards the left or west, away from the Prussians, as it went, the outposts of that western half of the allied army, which Wellington commanded.
We have seen that Napoleon, who had certainly arrived quickly and half-unexpectedly at the point of junction between Wellington’s scattered forces and those of the Prussians, when he crossed the Sambre at Charleroi, overestimated his success. He thought his enemy had even less notice of his advance than that enemy really had; he thought that enemy had had less time to concentrate than he had really had. Napoleon therefore necessarily concluded that his enemy had concentrated to a less extent than he actually had.
That mistake had the effect, in the case of the army of the right, which he himself commanded, of bringing him up against not one Prussian army corps but three. This accident had not disconcerted him, for he hoped to turn it into a general disaster for the Prussians, and to take advantage of their unexpected concentration to accomplish their total ruin. But such a plan was dependent upon the left-hand or western army, that upon the Brussels road under Ney, not finding anything serious in front of it. Ney could spare men less easily if the Emperor’s calculation of the resistance likely to be found on the Brussels road should be wrong. It was wrong. That resistance was not slight but considerable, and Ney was not free to come to Napoleon’s aid. Tardy as had been the information conveyed to the Duke of Wellington, and grievously as the Duke of Wellington had misunderstood its importance, there was more in front of Ney upon the Brussels road than the Emperor had expected. What there was, however, might have been pushed back—after fairly heavy fighting it is true, but without any risk of failure—but for another factor in the situation, which was Ney’s own misjudgment and inertia.
Napoleon himself said later that his marshal was no longer the same man since the disasters of two years before; but even if Ney had been as alert as ever, misjudgment quite as much as lack of will must have entered into what he did. He had thought, as the Emperor had, that there would be hardly anything in front of him upon the Brussels road. But there was this difference between the two errors: Ney was on the spot, and could have found out with his cavalry scouts quite early on the morning of Friday the 16th what he really had to face. He preferred to take matters for granted, and he paid a heavy price. He thought that there was plenty of time for him to advance at his leisure; and, thinking this, he must have further concluded that to linger upon that part of the Brussels road which was nearest the Emperor’s forthcoming action to the east by Ligny would be good policy in case the Emperor should have need of him there.
On the night of the 15th Ney himself was at Frasnes, while the furthest of his detachments was no nearer than the bridge of Thuin over the Sambre, sixteen miles away. The rough sketch printed opposite will show how very long that line was, considering the nearness of the strategical point Quatre Bras, which it was his next business to occupy. The Second Army Corps under Reille was indeed fairly well moved up, and all in the neighbourhood of Gosselies by the night between Thursday 15th and Friday 16th of June. But the other half of the force, the First Army Corps under Erlon, was strung out over miles of road behind.
To concentrate all those 50,000 men, half of them spread out over so much space, meant a day’s ordinary marching; and one would have thought that Ney should have begun to concentrate before night fell upon the 15th. He remembered, however, that the men were fatigued, he thought he had plenty of time before him, and he did not effect their concentration. The mass of the Second Army Corps (Reille’s) was, as I have said, near Gosselies on the Friday dawn; but Erlon, with the First Army Corps, was not in disposition to bring the bulk of it up by the same time. He could not expect to be near Quatre Bras till noon or one o’clock. But even to this element of delay, due to his lack of precision, Ney added further delay, due to slackness in orders.
