Friedrich II, Landgrave Of Hesse-Kassel

Frederick II of Hesse-Kassel, also known as Landgraf Friedrich II von Hessen-Kassel, was born on 14 August 1720 in Kassel, Hesse. He was the son of William VIII, Landgrave of Hesse-Kassel, and Dorothea Wilhelmine of Saxe-Zeitz. His paternal grandfather was Charles I, Landgrave of Hesse-Kassel, and his paternal uncle was Frederick I of Sweden. His early education was overseen initially by Colonel August Moritz von Donop and from 1726 to 1733 by Swiss theologian and philosopher Jean-Pierre de Crousaz.

On 8 May 1740, Friedrich was married by proxy in London, and on 28 June 1740 he married in person in Kassel Princess Mary, the fourth daughter of King George II of Great Britain and Caroline of Ansbach. The marriage produced four sons: William (born 25 December 1741, died 1 July 1742), William I, Elector of Hesse (born 3 June 1743), Charles (born 19 December 1744), and Frederick (born 11 September 1747). Charles was the grandfather of Princess Louise Caroline of Hesse-Kassel and of Christian IX of Denmark, while Frederick was the grandfather of Queen Louise of Denmark.

In December 1745, Frederick participated in military operations in support of his father-in-law, George II, in Scotland to suppress the Jacobite rising, deploying approximately 6,000 Hessian troops. Although he initially supported the Protestant succession during this period, he later converted to Catholicism in 1749 after visiting the Archbishop-Elector of Cologne, Clemens August of Bavaria. Prior to this, his religious upbringing was Calvinist, though his children were raised as Protestants in Denmark, where they lived after his separation from his wife.

Frederick's marriage to Princess Mary was strained; they were living apart from 1747 and officially separated in 1755. Mary moved to Denmark in 1756, where she cared for her late sister’s children. Her three surviving sons, including William, moved with her. William later married Danish princesses, while the younger sons remained in Denmark, where they held high court positions; William returned to Germany upon inheriting the principality of Hanau and later succeeded Frederick as Landgrave of Hesse-Kassel.

Frederick II married again on 10 January 1773 in Berlin to Margravine Philippine, daughter of Frederick William, Margrave of Brandenburg-Schwedt, and Sophia Dorothea of Prussia. No children resulted from this marriage.

He assumed the title of Landgrave of Hesse-Kassel in 1760 following the death of his father and ruled until his own death. His reign was characterized by the integration of Enlightenment ideas with Christian values and a cameralist approach to economic management. He is also recognized for maintaining a large military force, renting out troops—referred to as "Hessians"—to foreign powers, notably to Great Britain for use in the American Revolutionary War.

Frederick II’s rule saw the transformation of Kassel into a modern capital under the architect Simon Louis du Ry. He died on 31 October 1785 at Weißenstein Castle (Schloss Wilhelmshöhe) in Kassel. His successor was his eldest surviving son, William.