sentences:  In 1940, Belgian pre-war émigrés and former soldiers who had escaped occupied Belgium were formed into units within the British military which later fought in the European and Mediterranean Theatres.These included an infantry formation, which later became the "Brigade Piron", as well as Commando and paratroop units.Belgians also served in the Royal Air Force and Royal Navy, serving in Belgian-only units as well as in majority-British units.