Power, as Henry Kissinger gloated, is the ultimate aphrodisiac. At his star’s highest point in 1810 — he was then aged 41 — the Emperor Napoleon was the master of continental Europe, with 44 million people under his control. Then, in a moment of candor, he confessed to an aide that he had done it all not for glory, patriotism, or ego, but for love: As the world’s most powerful man, he could sleep with any woman he desired.

In the Emperor’s bedroom, however, the reviews were mixed. Just as he indifferently bolted down his food, paid no attention to his clothes, and could be self-absorbed and distracted in conversation, Napoleon’s romantic style, admits one otherwise admiring biographer, was “anything but endearing.” A description by the author Stendahl, backed up by members of Napoleon’s staff, describes his “brutally… More…