William Davidson (February 14, 1783 in Carlisle, Cumberland, Pennsylvania - 1867) was a Pennsylvania politician.
He served in the War of 1812, becoming a prisoner of war in the capture of Detroit under Hull. After that experience, he returned to Connellsville, where he married the widow Sarah Rogers Blackstone. They had five children. He served in the Pennsylvania House of Representatives, being elected as the Speaker of the House in 1818. He also served in the Pennsylvania Senate. He lived to the age of 84.