1850
Joseph Barker (People's and Anti-Catholic) became Pittsburgh's 17th mayor
Elected while in jail for inciting anti-Catholic and anti-Masonic riots. The itinerate preacher was released to serve his one-year mayoral term. Barker repeatedly sought re-election, but failed. Then, he was decapitated when he got too close to a train
1851
John B. Guthrie (democrat) became Pittsburgh's 18th mayor
1852
Beallsville became a municipality
1853
Robert M. Riddle (whig) became Pittsburgh's 19th mayor
1854
Ferdinand E. Volz (Whig-Democratic fusion (anti-Know Nothing)) became Pittsburgh's 20th mayor
1855
Carmichaels became a municipality
Carmichaels Borough was settled in 1767 and incorporated in 1855 from Cumberland Township. Carmichaels was laid out by James Carmichael, who was a scout and woodsman. He obtained the title of the land in a trade with Thomas Hughes who went to Jefferson.
1856
William Bingham (american) became Pittsburgh's 21st mayor
1857
Henry A. Weaver (republican) became Pittsburgh's 22nd mayor