This district in Uccle derives its name from Jacques "Jaco" Pasture (1659-1723). Born in Braine l'Alleud, he was a roving marksman who fought in the service of Spain, most notably in the environs of the Forêt de Soignes. A Spanish redoute was built here in 1705, to which the name Fort Jaco was applied in the 18th century in remembrance of his fame.
Historical Dictionary of Brussels. Paul F. State.