Francis, Duke of Saxe-Coburg-Saalfeld (Coburg, 15 July 1750 – Coburg, 9 December 1806), was one of the ruling Thuringian dukes of the House of Wettin. As progenitor of a line of Coburg princes who, in the 19th and 20th centuries, mounted the thrones of several European realms, he is a patrilineal ancestor of, among others, Queen Elizabeth II of the United Kingdom, King Philippe of Belgium and Simeon B. Sakskoburggotski, former tsar (Simeon II) and prime minister of Bulgaria.

He was the eldest son of Ernest Frederick, Duke of Saxe-Coburg-Saalfeld and Sophia Antonia of Brunswick-Wolfenbüttel.

He received a private, careful and comprehensive education and became an art connoisseur. Francis initiated a major collection of books and illustrations for the duchy in 1775, which eventually expanded to a 300,000 picture collection of copperplate engravings currently housed in the Veste Coburg.

He was commissioned into the allied army in 1793 when his country was invaded by the Revolutionary armies of France. The allied forces included Hanoverians, Hessians, and the British. He fought in several actions against the French.

Francis succeeded his father as reigning Duke of Saxe-Coburg-Saalfeld in 1800. In the discharge of his father's debts the Schloss Rosenau had passed out of the family but in 1805 he bought back the property as a summer residence for the ducal family.

Emperor Francis II dissolved the Holy Roman Empire on 6 August 1806, after its defeat by Napoleon at the Battle of Austerlitz. Duke Francis died 9 December 1806. On 15 December 1806, Saxe-Coburg-Saalfeld, along with the other Ernestine duchies, entered the Confederation of the Rhine as the Duke and his ministers planned.

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