In September 1898, the Empress of Austria—on holiday in Geneva, Switzerland—was stabbed and murdered by an Italian anarchist. The killing stunned Europe. Forty years later, the novelist Rebecca West still recalled her shock at the news. She explained her surge of emotion to a puzzled housemaid: “Assassinations lead to other things.”

But do they?

Sixteen years after that, the shooting of the empress’s nephew, the Archduke Franz Ferdinand, plunged Europe into the First World War. Yet Empress Elisabeth’s killing, every bit as atrocious, had no geopolitical effect at all. The empress’s murderer was tried as a common criminal and sentenced to life imprisonment. He committed suicide in 1910.

The difference in the two killings cannot be explained by emotion. The empress was a figure widely popular with the public and much loved by her husband, the emperor. The dour Archduke Franz Ferdinand was disliked by both. The shooting of the archduke led to war, not because anybody important grieved for him, but because the Austrian leadership in 1914 welcomed an excuse to punish Serbia for a string of provocations. Gavrilo Princip’s connections to Serbian nationalist groups provided that excuse. In 1898, by contrast, Austria had no appetite for a conflict with Italy—and so the cherished empress’s slaying was left to the ordinary processes of law.