Leopold IV, Prince of Lippe (Leopold Julius Bernhard Adalbert Otto Karl Gustav; 30 May 1871 – 30 December 1949) was the final sovereign of the Principality of Lippe. Succeeding to the throne in 1905 he had been governing the state since 1904 as regent. Early life He was born as Count Leopold of Lippe-Biesterfeld in Oberkassel, the son of Ernest, Count of Lippe-Biesterfeld and Countess Karoline of Wartensleben. Leopold belonged to the Lippe-Biesterfeld line of the House of Lippe which was the most senior line of the princely house after the reigning Lippe-Detmold line. He served as an officer in the German Army until 1894, when he left to study political science at the universities of Bonn and Berlin. Ruler of Lippe Since 1895, Lippe had been ruled by a regent due to the incapacity of Prince Alexander. Leopold's father had acted as regent since 1897, and following his death on 26 September 1904, Leopold assumed the regency. This was not recognized by the German Emperor William II, who initially refused to legally recognize Leopold as regent as there was an issue over whether Leopold and his siblings were of legitimate rank, and as such eligible for the succession. As a result, the Diet of Lippe appointed a high commission to consider the matter. The regency issue was still ongoing when Prince Alexander died on 13 January 1905. Leopold was confirmed as Prince of Lippe and Alexander's successor on 25 October 1905, following a court ruling. On 3 June 1911, while out motoring, Leopold and his brother Prince Julius were attacked by a gang of Italian laborers who hurled a shower of missiles at the princes. Though Leopold escaped unhurt, his brother received a head wound. During World War I, Leopold upgraded the titles of the various lines of the House of Lippe. One of the members to benefit from the granting of titles was Leopold's nephew Count Bernhard of Biesterfeld (son of Leopold's brother Bernhard), who would go on to become the Prince Consort of Queen Juliana of the Netherlands. On 24 February 1916, Bernhard and his brother were upgraded to the title Prince of Lippe-Biesterfeld with the style Serene Highness. The Counts of Lippe-Weissenfeld also benefited with creations of the title Prince of Lippe-Weissenfeld, with the style Serene Highness, taking place on 24 February 1916 for Count Clemens and his descendants, and again on 9 November 1918 for