List of Famous people who died in 1903

Cassius Marcellus Clay, nicknamed the "Lion of White Hall," was a Kentucky planter, politician, and emancipationist who worked for the abolition of slavery. He was a founding member of the Republican Party in Kentucky, and was appointed by President Abraham Lincoln as the United States minister to Russia. Clay is credited with gaining Russian support for the Union during the American Civil War.

James Glaisher FRS was an English meteorologist, aeronaut and astronomer.

Martha Jane Cannary, better known as Calamity Jane, was an American frontierswoman. In addition to many exploits she was known for being an acquaintance of Wild Bill Hickok. Late in her life, she appeared in Buffalo Bill's Wild West show and at the 1901 Pan-American Exposition. She is said to have exhibited compassion to others, especially to the sick and needy. This facet of her character contrasted with her daredevil ways and helped to make her a noted frontier figure. She was also known for her habit of wearing men's attire.

Helen Pitts Douglass (1838–1903) was an American suffragist, known for being the second wife of Frederick Douglass. She also created the Frederick Douglass Memorial and Historical Association.

Apolinario Mabini y Maranan was a Filipino revolutionary leader, educator, lawyer, and statesman who served first as a legal and constitutional adviser to the Revolutionary Government, and then as the first Prime Minister of the Philippines upon the establishment of the First Philippine Republic. He is regarded as the "utak ng himagsikan" or "brain of the revolution" and is also to be considered to be as the National Hero in the Philippines, he was able to persuade other heroes including José Rizal, the national hero of the Philippines. Mabini's work and thoughts on the government shaped the Philippines' fight for independence over the next century.

Eugène Henri Paul Gauguin was a French Post-Impressionist artist. Unappreciated until after his death, Gauguin is now recognized for his experimental use of color and Synthetist style that were distinct from Impressionism. Toward the end of his life, he spent ten years in French Polynesia. The paintings from this time depict people or landscapes from that region.

Phantly Roy Bean Jr. was an American saloon-keeper and Justice of the Peace in Val Verde County, Texas who called himself "The Only Law West of the Pecos". According to legend, he held court in his saloon along the Rio Grande on a desolate stretch of the Chihuahuan Desert of southwest Texas. After his death, Western films and books cast him as a hanging judge, although he is known to have sentenced only two men to hang, one of whom escaped.

Margaret Ann Neve was the first recorded female supercentenarian and the second validated human to reach the age of 110 after Geert Adriaans Boomgaard. Neve lived at Saint Peter Port on the island of Guernsey in the English Channel. She was also the first proven individual whose life spanned three centuries.

Josiah Willard Gibbs was an American scientist who made significant theoretical contributions to physics, chemistry, and mathematics. His work on the applications of thermodynamics was instrumental in transforming physical chemistry into a rigorous inductive science. Together with James Clerk Maxwell and Ludwig Boltzmann, he created statistical mechanics, explaining the laws of thermodynamics as consequences of the statistical properties of ensembles of the possible states of a physical system composed of many particles. Gibbs also worked on the application of Maxwell's equations to problems in physical optics. As a mathematician, he invented modern vector calculus.

Joseph Astbury Warbrick was a Māori rugby union player who represented New Zealand on their 1884 tour to Australia and later captained the 1888–89 New Zealand Native football team that embarked on a 107-match tour of New Zealand, Australia, and the British Isles.