Charles Alexander Augustus John, Grand Duke of Saxony (German: Carl Alexander August Johann; 24 June 1818 - 5 January 1901) was the ruler of Saxe-Weimar-Eisenach from 1853 until his death.
In The Hague, on 8 October 1842, Karl Alexander married with his first cousin, Princess Sophie of the Netherlands, daughter of William II and Grand Duchess Anna Pavlovna of Russia, sister of his mother. They had four children:
Karl August Wilhelm Nicolaus Alexander Michael Bernhard Heinrich Frederick Stefan, Hereditary Grand Duke of Saxe-Weimar-Eisenach (b. Weimar, 31 July 1844 - d. Cap Martin, France, 20 November 1894).
Marie Anna Alexandrine Sophie Auguste Helene (b. Weimar, 20 January 1849 - d. Trebschen, 6 May 1922), known as Marie; married on 6 February 1876 to Prince Heinrich VII Reuss.
Maria Anna Sophia Elisabeth Bernhardine Ida Auguste Helene (b. Weimar, 29 March 1851 - d. Weimar, 26 April 1859), known as Anna.
Elisabeth Sibylle Maria Dorothea Anna Amalie Luise (b. Weimar, 28 February 1854 - d. Wiligrad, 10 July 1908), known as Elisabeth; married on 6 November 1886 to Duke Johann Albrecht of Mecklenburg-Schwerin.
