Napoleon liked to think that he was a genius in everything. Where he was actually a genius was in his powers of memory, his tireless focus, and his mastery of military logistics: the movement of troops and supplies in war. He memorized things like the movement speed of his armies, the amount of and type of supplies needed by his forces, the rate at which they would lose men to injury, desertion, and disease, and how much ammunition they needed to have on hand. He was so skilled at map-reading that he could coordinate multiple army corps to march separately, miles apart, and then converge at a key moment to catch his enemies by surprise. He was indifferent to luxury and worked relentlessly, often sleeping only four or five hours a night, and his intellectual gifts (astonishing powers of memory foremost among them) were such that he was capable of effectively micro-managing his entire empire through written directives to underlings.

Unlike past revolutionary leaders, Napoleon faced no dissent from within his government or his forces, especially the army. Simply put, Napoleon was always able to rely on the loyalty of his troops. He took his first step toward independent authority in the spring of 1796, when he announced that his army would be paid in silver rather than the paper money issued by the French Republic that had lost almost all of its value. Napoleon led his men personally in most of the most important battles, and because he lived like a soldier like them, most of his men came to adore him. His victories kept morale high both among his troops and among the French populace, as did the constant stream of pro-Napoleonic propaganda that he promoted through imperial censorship.

Napoleon’s military record matched his ambition: he fought sixty battles in the two decades he was in power, winning all but eight (the ones he lost were mostly toward the end of his reign). His victories were not just because of his own command of battlefield tactics, but because of the changes introduced by the French Revolution earlier. The elimination of noble privilege enabled the French government to impose conscription and to increase the size and flexibility of its armies. It also turned the officer corps into a true meritocracy: now, a capable soldier could rise to command regardless of his social background. Mass conscription allowed the French to develop permanent divisions and corps, each combining infantry, cavalry, artillery, and support services. On campaign these large units of ten to twenty thousand men usually moved on separate roads, each responsible for extracting supplies from its own area, but capable of mutual support. This kind of organization multiplied Napoleon’s operational choices, facilitating the strategies of dispersal and concentration that bewildered his opponents.

In some ways, however, his strengths came with related weaknesses. In hindsight, it seems clear that his greatest problem was that he could never stop: he always seemed to need one more victory. While supremely arrogant, he was also self-aware and savvy enough to recognize that his rule depended on continued conquests. For the first several years of his rule, Napoleon appeared to his subjects as a reformer and a leader who, while protecting France’s borders, had ended the war with the other European powers and imposed peace settlements with the Austrians and the British which were favorable to France. By 1805, however, it was clear to just about everyone that he intended to create a huge empire far beyond the original borders of France.