Causes of mortality in the British Army between 1854 and 1856. This polar area chart is based on a diagram originally published in 1858 by British nurse Florence Nightingale (1820-1910). It depicts the causes of death of British soldiers fighting in the Crimean War. Blue wedges represent deaths from preventable epidemic diseases, red wedges represent deaths from battle wounds and black wedges represent deaths from other causes. This diagram, commonly known as the Nightingale rose, was created in collaboration with medical statistician William Farr. Nightingale's work helped prove that many deaths during war were preventable and led to improvements in patient care, discipline and sanitation.