|W. Thacher Longstreth|
|Member of the Philadelphia City Council from the At-Large District|
January 2, 1984 – April 11, 2003
|Preceded by||Beatrice Chernock|
|Succeeded by||Jack Kelly|
January 1, 1968 – January 3, 1972
|Preceded by||Virginia Knauer|
|Succeeded by||Beatrice Chernock|
January 1, 1920|
|Died||April 11, 2003
|Spouse(s)||Anne Nancy Claghorn|
|Alma mater||BA, Princeton University|
|Years of service||1942-1946|
|Battles/wars||World War II|
|Awards||Bronze Star (Two)|
Longstreth, a graduate of Princeton University, was an eighth-generation Philadelphian born to Quakers William C. (b. 1882) and Nella (née Thacher) Longstreth, whom William married in 1917. William C. Longstreth owned the Longstreth Motor Car Company and his family lived in Haverford, Pennsylvania, and was affluent until the Stock Market Crash of 1929. Thacher was a cousin of President Herbert Hoover and his maternal grandmother, Ella Hoover Thacher was the president of the Women's Christian Temperance Union for many years. In 1970, he led the Philadelphia Chamber of Commerce and spearheaded the drive to hold the annual Earth Day commemoration in Philadelphia. That event became one of the biggest Earth Day events in the nation. He was also instrumental in the creation of the Greater Delaware Valley Chapter of the National Multiple Sclerosis Society. He was predeceased by his half sister, Nella Cameron Downward (1913-1997). His younger brother, Frank Longstreth (b. 1922) died in 2008.
He was initially elected to Philadelphia's City Council in 1967, and left office to run for Mayor in 1971. Longstreth was again elected to Council in 1983, defeating incumbent councilwoman Beatrice Chernock for the at-large seat he had vacated twelve years earlier to run for Mayor. He would remain in office until his death. During his tenure on Council, Longstreth helped support the efforts of Edmund Bacon to bring an urban renaissance to Philadelphia. He was also well known for wearing bow ties and argyle socks.
- "Resolution No. 030269". Council of Philadelphia, Office of the Chief Clerk. City of Philadelphia. Retrieved February 7, 2012.
- "Chernock Loses Council Seat to Longstreth". The Philadelphia Inquirer. November 9, 1983. Retrieved February 7, 2012.
- Twyman, Anthony S. (March 13, 2003). "Longstreth abused, nurses say". The Philadelphia Inquirer. Retrieved February 7, 2012.
- "W. Thacher Longstreth, 82, 6-Term Philadelphia Councilman". The New York Times. April 12, 2003. Retrieved February 7, 2012.