Chatham Square is named after William Pitt, 1st Earl of Chatham (1708–1778), who is also the eponym of Pittsburgh itself.[1, 2, 3, 4] See also Beechwood Boulevard, which was named William Pitt Boulevard from 1910 to 1913, and Stanwix Street, the northern part of which was originally named Pitt Street.
A short street between Bigelow Boulevard and Centre Avenue, immediately west of Interstate 579, is identified by a sign at the Centre Avenue intersection as Chatham Street.
DeLaney, James K. “Spectres of past haunt Pittsburgh’s corner signposts: Street names ‘pennants of tribute.’” Pittsburgh Post-Gazette, Mar. 30, 1967, Daily Magazine, [p. 1]. Newspapers.com 88235360.
Miller, Annie Clark. Early Land Marks and Names of Old Pittsburgh: An address delivered before the Pittsburgh Chapter Daughters of the American Revolution at Carnegie Institute, Nov. 30, 1923. Pittsburgh Chapter Daughters of the American Revolution, 1924, p. 26. Historic Pittsburgh 00awn8211m; Internet Archive earlylandmarksna00mill.
Regan, Bob. The Names of Pittsburgh: How the city, neighborhoods, streets, parks and more got their names. The Local History Company, Pittsburgh, 2009, p. 66. ISBN 978-0-9770429-7-5.
“Street names sketch history of city: Tribute to many pioneers dimmed by time.” Pittsburgh Post-Gazette, Sept. 26, 1936, anniversary section IV, p. 16. Newspapers.com 88921069.