Born in Montgomery County, Pennsylvania, Miles was the son of James Miles and Hannah Pugh. Miles enlisted in Isaac Wayne's company, part of the Pennsylvania militia during the French and Indian War. He was wounded at the Battle of Fort Ligonier; later commanding the garrison at that fort. He was discharged and then reenlisted in Thomas Lloyd's company as a sergeant and was promoted to captain-lieutenant for the expedition to Fort Duquesne. He accepted a commission as captain in 1760 and commanded troops on Presque Isle. After the war ended, he went into business as a wine merchant and married Catherine Wister, daughter of John Wister of Grumblethorpe, Philadelphia, PA. He also entered politics, and was elected to the house of assembly in 1772. He was an early advocate for American independence.
Miles raised a militia company in the early days of the American Revolution. When the war began, he was made colonel of the Pennsylvania State Rifle Regiment, a state unit later adopted into the Continental Army. He was taken prisoner by the British at the Battle of Long Island. Miles was released as part of a prisoner exchange in April 1778 that included British Lieutenant Colonel Archibald Campbell. He had been appointed brigadier general of Pennsylvania state troops while a prisoner. Upon his release he served as quartermaster for the State of Pennsylvania  serving under Timothy Pickering. In the summer of 1781 General Washington counted on Miles to secure boat transport for the army as it made its way south from New York to Yorktown.
After the war
After the war, Miles had a distinguished career as a politician and public servant. He was made judge of the Appeals Court, served as an alderman and mayor of Philadelphia from 1790 to 1791. He was reelected as mayor but declined. He was elected trustee for the University of Pennsylvania, resigning in 1793. He was also a member of American Philosophical Society and very active in the First Baptist Church of Philadelphia. The town of Milesburg, Pennsylvania, was laid out by him and is named after him.
As a businessman in 1783 he operated an early sugar refinery with Colonel Jacob Morgan at 77 Vine Street in Philadelphia. Joining with financier Robert Morris, he helped underwrite the voyage of the ship - The Empress of China - the first American vessel to visit the Chinese mainland. In 1791 with John Patton he was co-founder of Centre Furnace in State College, Pennsylvania.
Miles is also noted as being the first faithless elector, when he was pledged to vote for Federalist presidential candidate John Adams, but voted for Republican candidate Thomas Jefferson. This was the first contested election in USA and an angry voter wrote to the Gazette of the United States, "What! Do I chuse Samuel Miles to determine for me whether John Adams or Thomas Jefferson shall be President? No! I chuse him to act, not to think!" Miles cast his other presidential vote as pledged for Thomas Pinckney.
As a new member of the Democratic-Republican party he ran for Congress twice (1798) losing to political newcomer Federalist Robert Waln (1765–1836).
His portrait, painted by noted American artist Gilbert Stuart, is housed in the Washington, DC Corcoran Gallery of Art. The portrait of his wife, Catherine Wister Miles, was also completed by Gilbert Stuart. Another portrait of Samuel Miles, completed by Charles Willson Peale, is in the Philadelphia Museum of Art.
- Appendix II: Pennsylvania Archives; Series 5, Vol. 7, P. 249;PENNSYLVANIA RIFLE REGIMENT; COLONEL SAMUEL MILES; MARCH 6, 1776
- Robert Morris, John Catanzariti;The Papers of Robert Morris, 1781-1784, Volume 7
- Robert Morris, Elmer James; The Papers of Robert Morris, 1781-1784: August–September 1781 page 118
- Members of the Society of the Cincinnati. William Sturgis Thomas. 1929.
- Samuel Miles Papers, American Philosophical Society; 1776-1802;16.0 Item(s); Mss.B.M589
- November 1943 C. A. Browne, J. Chem. Educ., 1943, 20 (11), p 522
|Member, Supreme Executive Council of Pennsylvania, representing the City of Philadelphia
20 October 1788–20 December 1790
|Mayor of Philadelphia