Ernst I, Duke of Saxe-Coburg-Saalfeld, later Duke of Saxe-Coburg-Gotha, (January 2, 1784 – January 29, 1844) was the son of Duke Francis Frederick of Saxe-Coburg-Saalfield (1750-1806) and Countess Auguste Reuss zu Ebersdorf und Lobenstein (1757-1831).

On July 3, 1817, he married Luise, Princess of Saxe-Gotha (1800-1831) at Gotha. They were divorced in 1826.

On December 23, 1832 he married his niece, Marie, Duchess of Württemberg (1799-1860) at Coburg.

He had two children by his first wife:

• Ernst II, Duke of Saxe-Coburg-Gotha (1818-1893)
• Albert, Prince Consort of the United Kingdom (1819-1861)

Dukes of Saxe-Coburg and Gotha | 1784 births | 1844 deaths

Ernst I. (Sachsen-Coburg und Gotha) | Ernst I van Saksen-Coburg en Gotha | Ernst I av Sachsen-Coburg-Gotha | Ernst I av Sachsen-Coburg-Gotha