Earthquakes That Changed History

On November 1, 1755 — All Saints' Day — a magnitude 8.5-9.0 earthquake struck Lisbon, Portugal. It lasted up to six minutes. Churches packed with worshippers collapsed. A tsunami followed within 40 minutes, flooding the lower city. Then fires burned for five days. An estimated 60,000 people died, and the disaster shattered European optimism.

Philosophers like Voltaire used the catastrophe to challenge the idea that we live in the best of all possible worlds. The Marquis de Pombal launched one of history's first scientific earthquake investigations, sending questionnaires across the country to record how long the shaking lasted, which way buildings fell, and how the sea behaved. His findings shaped how Lisbon was rebuilt.