It was commanded from 1808 to 1814 by Major (later LtCol) George Scovell, seconded from the Portuguese Quartermaster-General's Department.

Later recruits were generally of foreign deserters and Spaniards in order to gather information for the Anglo-Portuguese Army in Spain and southern France.

In the 1812-1814 campaigns the Corps of Mounted Guides was increasingly tasked with transmission of despatches, and also became more involved in provost duties.

It would also seem to indicate that the guides wore the colours of the British Quartermaster-General's Department: scarlet faced with blue, with white or silver buttons and lace.

Osprey Publishing - Men-At-Arms 343 - Portuguese Armies Of The Napoleonic Wars (1), by René Chartrand and Bill Younghusband