Adolphus Frederick VI, Grand Duke of Mecklenburg-Strelitz (1882–1918). Duke Karl Borwin of Mecklenburg-Strelitz (Karl Borwin Christian Alexander Arthur, Herzog von Mecklenburg-Strelitz;  10 October 1888 – 24 August 1908); killed in a duel with his brother-in-law Count George Jametel, defending his sister's honor.
The Grand Duchy of Mecklenburg-Strelitz was a territory in Northern Germany, held by the younger line of the House of Mecklenburg residing in Neustrelitz.Like the neighbouring Grand Duchy of Mecklenburg-Schwerin, it was a sovereign member state of the German Confederation and became a federated state of the North German Confederation and finally of the German Empire upon the unification of 1871.
Grand Duchy of Mecklenburg-Strelitz (1815–1918, joined the German Empire in 1871) Grand Duchy of Posen (1815–1848 as a de facto part of Prussia (nominally ruled in a personal union), Großherzogtum Posen) Grand Duchy of Saxe-Weimar-Eisenach (1815–1918, joined the German Empire in 1871)
In 1815, the two Mecklenburgian duchies were raised to Grand Duchies, the Grand Duchy of Mecklenburg-Schwerin and the Grand Duchy of Mecklenburg-Strelitz, and subsequently existed separately as such in Germany under enlightened but absolute rule (constitutions being granted on the eve of World War I) until the revolution of 1918.
He was born in Schwerin, Duchy of Mecklenburg-Schwerin, to Duke Louis of Mecklenburg-Schwerin and Princess Charlotte Sophie of Saxe-Coburg-Saalfeld. Friedrich Franz succeeded his uncle Friedrich as duke of Mecklenburg-Schwerin in 1785. Following the Napoleonic Wars, Friedrich Franz was raised to the dignity of grand duke at the Congress of Vienna.
The Grand Duchy originally formed from the Landgraviate of Hesse-Darmstadt in 1806 as the Grand Duchy of Hesse (German: Großherzogtum Hessen). It assumed the name Hesse and bei Rhein in 1816 to distinguish itself from the Electorate of Hesse , which had formed from neighbouring Hesse-Kassel .
Charlotte of Mecklenburg-Strelitz (Sophia Charlotte; 19 May 1744 – 17 November 1818) was Queen of Great Britain and of Ireland as the wife of King George III from their marriage on 8 September 1761 until the union of the two kingdoms on 1 January 1801, after which she was Queen of the United Kingdom of Great Britain and Ireland until her death in 1818.