Napoleon had thus a powerful force immediately in front of the point which Blucher had fixed for the concentration of the Prussian army, and that concentration was still incomplete. The French Emperor designed to attack the Prussians on the morrow in person, with the troops of his centre and right columns, and to employ his left wing in beating back such English troops as might advance to the help of their allies, and also in aiding his own attack upon Blucher. He gave the command of this left wing to Marshal Ney. Napoleon seems not to have originally intended to employ this celebrated General in the campaign. It was only on the night of the 11th of June, that Marshal Ney received at Paris an order to join the army. Hurrying forward to the Belgian frontier, he met the Emperor near Charleroi. Napoleon immediately directed him to take the command of the left wing, and to press forward with it upon Quatre Bras by the line of the road which leads from Charleroi to Brussels, through Gosselies, Frasne, Quatre Bras, Genappe, and Waterloo. Ney immediately proceeded to the post assigned him; and before ten on the night of the 15th he had occupied Gosselies and Frasne, driving out without much difficulty some weak Belgian detachments which had been stationed in those villages. The lateness of the hour, and the exhausted state of the French troops, who had been marching and fighting since ten in the morning, made him pause from advancing further to attack the much more important position of Quatre Bras. In truth, the advantages which the French gained by their almost superhuman energy and activity throughout the long day of the 15th of June, were necessarily bought at the price of more delay and inertness during the following night and morrow, than would have been observable if they had not been thus overtasked. Ney has been blamed for want of promptness in his attack upon Quatre Bras; and Napoleon has been criticised for not having fought at Ligny before the afternoon of the 16th: but their censors should remember that soldiers are but men ; and that there must be necessarily some interval of time, before troops, that have been worn and weakened by twenty hours of incessant fatigue and strife, can be fed, rested, reorganized, and brought again into action with any hope of success.

Having on the night of the 15th placed the most advanced of the French under his command in position in front of Frasne, Ney rode back to Charleroi, where Napoleon also arrived about midnight, having returned from directing the operations of the centre and right column of the French. The Emperor and the Marshal supped together, and remained in earnest conversation till two in the morning. An hour or two afterwards Ney rode back to Frasne, where he endeavoured to collect tidings of the numbers and movements of the enemy in front of him; and also busied himself in the necessary duty of learning the amount and composition of the troops which he himself was commanding. He had been so suddenly appointed to his high station, that he did not know the strength of the several regiments under him, or even the names of their commanding officers. He now caused his aides-de-camp to prepare the requisite returns, and drew together the troops, whom he was thus learning before he used them.

Wellington remained at the Duchess of Richmond's ball at Brussels till about three o'clock in the morning of the 16th, "showing himself very cheerful" as Baron Muffling, who accompanied him, observes. [Muffling, p. 233.] At five o'clock the Duke and the Baron were on horseback, and reached the position at Quatre Bras about eleven. As the French, who were in front of Frasne, were perfectly quiet, and the Duke was informed that a very large force under Napoleon in person was menacing Blucher, it was thought possible that only a slight detachment of the French was posted at Frasne in order to mask the English army. In that event Wellington, as he told Baron Muffling, would be able to employ his whole strength in supporting the Prussians: and he proposed to ride across from Quatre Bras to Blucher's position, in order to concert with him personally the measures which should be taken in order to bring on a decisive battle with the French. Wellington and Muffling rode accordingly towards Ligny, and found Marshal Blucher and his staff at the windmill of Bry, near that village. The Prussian army, 80,000 strong, was drawn up chiefly along a chain of heights, with the villages of Sombref, St. Amand, and Ligny in their front. These villages were strongly occupied by Prussian detachments, and formed the keys of Blucher's position. The heads of the columns which Napoleon was forming for the attack, were visible in the distance. The Duke asked Blucher and General Gneisenau (who was Blucher's adviser in matters of strategy) what they wished him to do, Muffling had already explained to them in a few words the Duke's earnest desire to support the Field-Marshal, and that he would do all that they wished, provided they did not ask him to divide his army, which was contrary to his principles. The Duke wished to advance with his army (as soon as it was concentrated) upon Frasne and Gosselies, and thence to move upon Napoleon's flank and rear. The Prussian leaders preferred that he should march his men from Quatre Bras by the Namur road, so as to form a reserve in rear of Blucher's army. The Duke replied, "Well, I will come if I am not attacked myself," and galloped back with Muffling to Quatre Bras, where the French attack was now actually raging.