William Davidson (February 14, 1783 – March 2, 1867) was an American politician from Pennsylvania who served as a Democratic member of the Pennsylvania House of Representatives from 1814 to 1818 including as Speaker of the House from 1817 to 1818 and as an Independent Republican member of the Pennsylvania Senate for the 17th district from 1817 to 1824.
He served as prothonotary and worked as manager of the Laurel Furnace in Bedford County, Pennsylvania.
In 1808, he moved to Connellsville, Pennsylvania, and worked as ironmaster at the Breakneck Furnace.
He served in the War of 1812 and was held as a prisoner of war after Fort Detroit was surrendered by William Hull.
After the war, he returned to Connellsville, married the widow Sarah Rogers Blackstone and together they had five children.