Richardson was born in Cincinnati, Ohio in 1856. He was the son of Albert D. Richardson (a journalist and Union spy during the American Civil War), and Mary Louise Pease. The young Richardson was known to be of a "temperamental" disposition from an early age.
When 16, Richardson began working for the Chicago Inter Ocean Newspaper; and later became a European correspondent for the Boston Herald. In addition to other newspaper and magazine posts, he served as managing editor of The Morning Telegraph when that newspaper was first founded. He was known for changing jobs often.
In 1884 he founded The Journalist trade magazine with C.A. Byrne.
Later in life, he joined the staff of The New York Times.
Richardson was best known as a writer on theatrical topics, which he focused on for thirty years. He also became a playwright, writing seven plays and three books. An early example of this work was the play, Anselma, which opened at New York's Madison Square Theatre in September 1885, for which he was the bookwriter.
Richardson died of pneumonia in February 1918. His obituary in the Fourth Estate, a journal on the newspaper industry, called Richardson "one of the most widely known dramatic editors in this country."
- Leander Richardson Dead. Dramatist and Theatrical Writer a Victim of Pneumonia; article; The New York Times; accessed .
- Obituary Notes; February 9, 1918 article; The Fourth Estate; accessed .
- American Vaudeville, Its Life and Times; 1940 article by Gilbert, Douglas; p.154; accessed .
- Fifty Years in Theatrical Management; 1912 article by Leavitt, Michael Bennett; pp. 612–13; accessed .
- Lee, Alfred McClung. The Daily Newspaper in America, Vol. 1, p. 228 (1937)
- "I Know .. because I Was There": Leander P. Richardson Reports the Black Hills Gold Rush; PDF download; 2001; McLaird, James. D.; "South Dakota History", Vol. 31.
- They Called Him Wild Bill: The Life and Adventures of James Butler Hickok; Book; Rosa, Joseph G.; pp. 268–269; accessed November 2013; ISBN 978-0-8061-1538-2.
- Anselma; IBDB; accessed November 2013.
- Leander Richardson; Amazon.com; accessed November 2013.