William Stephens Smith entered the Continental Army during the Revolution and became John Sullivan's aide in 1776. Wounded while carrying orders at Harlem Heights, he later commanded troops at Monmouth, Rhode Island and Springfield and served in the expedition against the Haudenosaunee. He joined Lafayette's staff and became Washington's aide in July 1781, serving during the Yorktown campaign. He subsequently supervised prisoners and helped oversee the British evacuation of New York.

In 1785 Smith became secretary to the American legation in London under John Adams. He married Adams's daughter Abigail Amelia the following year and returned to America in 1788. Washington appointed him U.S. marshal for New York in 1789; he later became supervisor of revenue. Land speculation brought financial difficulties, while his military connections secured a lieutenant colonelcy during the confrontation with France in the late 1790s.

Appointed surveyor of the port of New York in 1800, Smith lost the post after helping organize Francisco de Miranda's expedition against Spanish Venezuela in 1806. Prosecuted for violating American neutrality, he was acquitted. He then settled on a farm at Lebanon, New York. Elected as a Federalist to the U.S. House, he served from 1813 to 1815. Although he presented credentials for another term, he did not qualify, and Westel Willoughby successfully contested the election. Smith died in June 1816, after a career of military service and financial reverses.