Background
Louis was born at Grabow, Mecklenburg-Schwerin, third child and second son of Christian Ludwig II, Duke of Mecklenburg-Schwerin (1683–1756), (son of Frederick, Duke of Mecklenburg-Grabow and Landgravine Christine Wilhelmine of Hesse-Homburg) and his wife, Duchess Gustave Caroline of Mecklenburg-Strelitz (1694–1748), (daughter of Adolphus Frederick II, Duke of Mecklenburg-Strelitz and Duchess Marie of Mecklenburg-Güstrow).