The currents of History run deep and often unseen beneath the everyday ripple of events. But now and again the current rises to the surface, and the events of a single day shed an exceptional light on the meaning of the past.

Such events are the subject of Days that Changed the World. Some of the 50 days described here mark the end of an era; others the start of something new. Many are the dates of bloody battles or murders; others of momentous decisions or breathtaking discoveries. All are remembered as powerful symbols of their time.

Our story begins almost 2500 years ago on 28 September 480 before the Christian Era, when the Athenian navy destroyed the Persian invasion fleet in the Bay of Salamis. Had the Persians won we might never have heard the names of Plato, Aristotle or Alexander, nor recognize the word democracy. Charting 50 such defining moments, concluding with Nelson Mandela's release from prison in 1990 and 9/11 a decade after, Days that Changed the World is a unique and fascinating way to portray the story of world history.