The Duke of Brabant was the formally ruler of the Duchy of Brabant since 1183/1184. The title was created by the German Emperor Frederick Barbarossa in favor of Henry I of the House of Reginar, son of Godfrey III of Leuven (who was Duke of Lower Lotharingia at that time). The Duchy of Brabant was a feudal elevation of the since 1085/1086 existing title of Landgrave of Brabant. This was an Imperial fief which was assigned to Count Henry III of Leuven shortly after the death of the preceding Count of Brabant, Count Palatine Herman II of Lotharingia (born 20 September 1085). Although the corresponding county was quite small (limited to the territory between the rivers Senne and Dender) its name was applied to the entire country under control of the Dukes from the 13th century on. In 1190, after the death of Godfrey III, Henry I also became Duke of Lotharingia. Formerly Lower Lotharingia, this title was now practically without territorial authority, but was borne by the later Dukes of Brabant as an honorific title.