William Lilly (1602–1681) produced uncannily accurate forecasts about the country’s fortunes during the Civil War and predicted the Great Fire of London. Highlighting the links between prophecy and politics in a tumultuous age, this biography describes how Lilly rose from humble farming origins to become an astrologer consulted by both King and Parliament, how he produced his prophecies and evaded efforts to silence him, and how his almanacs and astrological guidebook influenced popular culture.