- May 1 William Steele, American Brigadier General (Confederate Army), born in Albany, New York (d. 1885)
- May 3 Nicola De Giosa, Italian composer, born in Bari, Italy (d. 1885)
- May 5 Stanisław Moniuszko, Polish conductor, composer (Straszny dwór - The Haunted Manor), and teacher, born in Ubiel, Minsk Governate, Russian Empire (now Belarus) (d. 1872)
- May 15 Thomas Leonidas Crittenden, American lawyer, politician, and Major General (Union Army), born in Russellville, Kentucky (d. 1893)
- May 16 Daniel Ammen, Capt (Union Navy), (d. 1898)
- May 17 Johann Nepomuk Kafka, Bohemian pianist and composer, born in Neustadt an der Mettau (d. 1886)
- May 18 Julius Hopp, Austrian composer, born in Vienna (d. 1885)
Queen Victoria
May 24 Queen Victoria, Queen of the United Kingdom and Ireland (1837-1901), born in London (d. 1901)
Walt Whitman
May 31 Walt Whitman, American poet (Leaves of Grass) and volunteer nurse during the Civil War, born in West Hills, New York (d. 1892)