Rittmeister (German for "Ride master" or "Cavalry master") was a military rank of a commissioned cavalry officer in the armies of Germany, Austria-Hungary, Scandinavia, and some other states. He would typically be in charge of a squadron (troop in the United States), and was the equivalent of a Captain (Hauptmann).
In Germany many pilots of the Imperial German Air Service during World War I were recruted from the cavalry of the German Army, they therefore often held the rank of Rittmeister, the "Knights Of The Skys" (German: Ritter der Lüfte) used their planes as "dueling horses with wings".
The Dutch equivalent, Ritmeester, still serves as the official designation for officers in the cavalry branches of the Royal Dutch Army. The Norwegian equivalent, Rittmester, still serves as the official designation for officers in the armoured and mechanized infantry branches of the Norwegian Army. In Sweden the rank was known as Ryttmästare, and in Denmark (until 1951) as Ritmester.
- A squadron was historically a cavalry sub unit. The term is still used to refer to modern cavalry units but can also be used as a designation for other arms and services. It should not be confused with squad.