Horatio Nelson Pool was born in Haddonfield, New Jersey on January 16, 1884. At the age of 10, his family moved to Philadelphia, and he studied at the M Street High School. He attended Philadelphia's School of Industrial Design, and later to Pennsylvania Academy of the Fine Arts.
Poole was a painter, printmaker, muralist and teacher, but he was well known for his mural paintings and his intaglio prints. He worked for the Work's Progress Administration, and he painted a 20-foot mural in San Francisco's Roosevelt Jr. High School during the 1930s.
He exhibited at the Fine Arts Museums of San Francisco, the Honolulu Museum of Art, the Isaacs Art Center, Mills College, and the Oakland Museum of California. Many museums still hold a collection of his work. He passed away in 1949.