Francis I

Francis I spent his entire reign in a financial death spiral, borrowing astronomical sums from Jacob Fugger and other bankers to fund a lifestyle so extravagant it made Versailles look modest. While peasants starved, he imported Italian artists, built châteaux that served no purpose except showing off, and threw parties that cost more than most kingdoms' annual budgets. The Fuggers alone held French debt equivalent to several years of royal revenue, making Francis less a sovereign than a very expensive client.

But Francis's real obsession wasn't art or architecture—it was beating Charles V, the Holy Roman Emperor, at everything. When Charles got elected Emperor partly through Fugger financing, Francis declared he'd outshine him or die trying. He launched ruinously expensive wars in Italy, captured Milan briefly, then lost it along with most of his army's treasury. At the Battle of Pavia in 1525, Francis was captured and held for ransom, forcing France to mortgage its future to foreign bankers just to get their king back.

The final irony came in 1547, when Francis died from what most historians believe was syphilis—the disease he'd probably contracted during his legendary debauchery. But his rotting, infected corpse became an accidental public health campaign. Courtiers who witnessed his agonizing death spread such vivid descriptions of syphilis's final stages that sexual behavior across European courts changed practically overnight. Nobles who'd previously considered multiple mistresses a mark of sophistication suddenly embraced relative monogamy.

Francis had spent thirty-two years trying to make France the envy of Europe through borrowed magnificence. Instead, his diseased death accomplished what no royal decree could: it terrified an entire continent into avoiding the plague that was killing kings and commoners alike.