The famous nurse known for her contributions to healthcare in the 19th century is Florence Nightingale. Often regarded as the founder of modern nursing, Nightingale dramatically improved sanitary conditions in hospitals during the Crimean War, drastically reducing the mortality rate of wounded soldiers. Her pioneering work emphasized the importance of hygiene, proper nutrition, and patient care, leading to the establishment of nursing as a respected profession. Nightingale also advocated for health reform and founded the first secular nursing school, greatly influencing nursing education and public health practices.