On August 13, 1910, Florence Nightingale died as the most famous nurse in British history, remembered for a lamp she barely carried. Her real legacy was data: statistical diagrams that forced the British Army to admit its soldiers were dying of neglect, not battle wounds. A century later, historians are still fighting over whether another Crimean War nurse, Mary Seacole, was unjustly erased from that story, or whether her modern revival has gone too far the other way.