Claim: The longest reigning Princess of Thurn and Taxis was Margarethe Klementine of Austria, while the shortest reigning Princess of Thurn and Taxis was Charlotte Louise de Lorraine, Countess de Lambesc.
Evidence: Margarethe Klementine of Austria 15 July 1890 22 January 1952
husband's death Charlotte Louise de Lorraine, Countess de Lambesc 22 March 1745 6 January 1747 Anna Adelheid of Fürstenberg-Heiligenberg 1695
husband's creation as Prince 13 November 1701 Anna Augusta of Hohenlohe-Waldenburg-Schillingsfürst 21 November 1703 21 September 1711 Maria Ludovika Anna of Lobkowicz 21 February 1714
husband's ascession 8 November 1739
husband's death Maria Henriette Josepha of Fürstenberg-Stühlingen 21 September 1750 4 June 1772 Auguste Elisabeth of Württemberg 17 March 1773
husband's ascession 1776
divorce Therese of Mecklenburg-Strelitz 13 November 1805
husband's ascession 15 July 1827
husband's death Wilhelmine of Dörnberg 24 August 1828 14 May 1835 Mathilde Sophie of Oettingen-Oettingen and Oettingen-Spielberg 24 January 1839 10 November 1871
husband's death Isabel Maria of Braganza 22 January 1952
husband's ascession 12 January 1970 Gloria of Schönburg in Glauchau and Waldenburg 26 April 1982
husband's ascession 14 December 1990
husband's death