noon
Therefore it was not until two o'clock in the afternoon that Napoleon advanced with sixty thousand men to attack the Prussians at Ligny , while at about the same hour the column under Ney advanced from Frasnes against Quatre Bras . The delay was fatal to Napoleon 's plans . Had the battles commenced at daybreak , Ney could have brushed aside the defenders of Quatre Bras , and would have been at Mount St. Jean by the time the English came up . The Prussians would have been beaten by noon instead of at dusk , and before nightfall their retreat would have been converted into a rout , and on the following day Napoleon 's whole army would have been in a position to have fallen upon the only British divisions that Wellington could by that time have collected to oppose him , and would probably have been in possession of Brussels before night . Thus , while the delay in sending news to Wellington prevented the allies combining against the French on the 16th of June , the delay of Napoleon in attacking that morning more than counterbalanced the error . There was the less excuse for that delay , inasmuch as he had himself chosen his time for fighting , and should not have advanced until he had his whole force well up and ready for action ; and as the advance during the first day 's fighting had been so slow , the whole army might well have been gathered at nightfall round Fleurus ready to give battle at the first dawn of day . Fighting as he did against vastly superior forces , Napoleon 's one hope of success lay in crushing the Prussians before the English -- who , as he well knew , were scattered over a large extent of country -- could come up , and his failure to do this cost him his empire .