Smilie was born in Ireland and immigrated on May 24, 1762, settling first in Lancaster County. He moved to Fayette in 1780.
He was a prominent Jeffersonian and was identified with the "'Quid" branch of the party. In 1806–07, during the debates over the abolition of the slave trade, Smilie was among the most outspoken against the evils of the slave trade. He argued that slaves illegally imported after 1808 should be freed, and that slave smugglers deserved the death penalty. Neither provision was adopted.
Congress
He was elected to the Thirteenth Congress in 1812 but died before it opened.
Everett, Edward. "John Smilie, Forgotten Champion of Early Western Pennsylvania." Western Pennsylvania Historical Magazine 33 (September–December 1950), 77–89.