Landgrave (Dutch landgraaf, German Landgraf; French landgrave; Latin comes magnus, comes patriae, comes provinciae, comes terrae, comes principalis, lantgravius) was a title used in the Holy Roman Empire and later on by its former territories. The title refers to a count who had feudal duty directly to the Holy Roman Emperor. His jurisdiction stretched over a sometimes quite considerable territory, which was not subservient to an intermediate power like a Duke, a Bishop or Count Palatine. The title survived from the times of the Holy Roman Empire (first records in Lower Lotharingia from 1086 on: Henry III of Leuven as landgrave of Brabant). A landgrave by definition exercised sovereign rights. His decision-making power was comparable to that of a Duke.
Landgrave occasionally continued in use as the subsidiary title of such nobility as the Grand Duke of Saxe-Weimar, who functioned as the Landgrave of Thuringia in the first decade of the 20th century, but the title fell into disuse after World War I.
The jurisdiction of a landgrave was a landgraviate and the wife of a landgrave was a landgravine. Examples: Landgrave of Thuringia, Landgrave of Hesse, Princely (Gefürsteter) Landgrave of Leuchtenberg (around a Bavarian castle; later made a duchy).
Landgraviate refers to the rank, office, or territory held by a landgrave.
Landgravine (German: Landgräfin) refers to the wife of a Landgrave or one who exercises the office or holds the rank in her own right.