In 1775, at the age of 33, Jonathan Smith joined the 1st Regiment of Connecticut Volunteers in response to the alarm at Lexington and Concord. His regiment then marched through northern New York to attack Montreal.
He was discharged in Montreal in the winter of 1776 with sickness. He returned to his loving wife Bethia Doolittle Smith and his children. Then in May of 1777, he reenlisted in the 5th Regiment of the Connecticut Line. He was killed in action 5 months later at the Battle of Germantown PA, serving with General Washington's troops. His burial site was never located.
In April, 2003, a memorial headstone was placed for him at Saratoga National Veteran's Cemetery, Schuylerville, NY.