Treaty of San Ildefonso (August 19, 1796). Military alliance between Spain and France to maintain a joint policy against Great Britain. As representatives, Manuel Godoy in the name of Charles IV of Spain and General Catherine Dominique de Perignon, emissary of the French Directory. Before the signing of this treaty, Spain was part of the First Coalition. After the Treaty of San Ildefonso in 1796, Spain switched sides and fought alongside the French Republic against the Coalition. Alliance of San Ildefonso. Allegorical engraving by Martinez. Historia del Levantamiento, guerra y revolucion de Espana by the Conde de Toreno. Madrid, 1851.