His maternal grandparents were Anselm Franz, 2nd Prince of Thurn and Taxis (30 January 1681 – 8 November 1739) and Princess Maria Ludovika Anna von Lobkowicz (20 October 1683 – 20 January 1750). Maria Ludovika was daughter of Prince Ferdinand August Leopold von Lobkowicz-Sagan (1655–1715) and Princess Maria Anna Wilhelmine of Baden-Baden (1655-1702).
He married (initially morganatically) Countess Sophie Albertine von Beichlingen (15 December 1728 – 10 May 1807), a daughter of August Gottfried Dietrich, Count of Beichlingen (1703–1769) and his wife, Sophie Helene, Baroness of Stöcken (1710–1738). Louis and Sophie had three daughters:
Henriette Charlotte Friederike (11 March 1767 – 23 May 1817), married Prince Karl Joseph von Hohenlohe-Bartenstein-Jagstberg (12 Dec 1766 – 6 Jul 1838)
Reign
He succeeded his brother Karl Eugen as Duke of Württemberg in 1793, and reigned until his own death in 1795, when he was succeeded by his younger brother Frederick Eugen.