Alexander Hay (April 8, 1806 – November 5, 1882), served as Mayor of Pittsburgh from 1842 to 1845.
Hay was born in the neighborhood known as Scotch Hill. By age eleven, he worked in a glass house and learned the trade of cabinetry.
The Roman Catholic Diocese of Pittsburgh was created during Mayor Hay's term. Also, navigation on the Monongahela River was opened as far south as Brownsville during his administration.
Hay's life of public service continued after his term as mayor. He commanded the Jackson Blues during the Mexican War. During the Civil War, he was Captain of Company E. PA. Regiment. He served at the Battle of Yorktown.
He and his son were the proprietors of a fine furniture business. Mayor Hay died in 1882 and is buried in the Allegheny Cemetery.
- List of Mayors of Pittsburgh
|- style="text-align: center;"
|width="30%" align="center" rowspan="1"|Preceded by
James Thompson |width="40%" style="text-align: center;" rowspan="1"|Mayor of Pittsburgh
1842–1845 |width="30%" align="center" rowspan="1"| Succeeded by
William J. Howard |- |}