- The belief or ideology that a unified Iberian Peninsula in which Spain and Portugal would be incorporated in the same political unit would enhance those countries' place in Europe, lay a basis for revival of the Iberian states from a position of decline, and lead to needed social improvements. Iberianism became popular with certain leftist groups, including socialists, in both countries in the 19th century, although it was a more popular idea in Spain than it was in Portugal. Sometimes Iberianism was expressed in the form of advocating an Iberian federal union or federation.
Historical dictionary of Portugal 3rd ed.. by Douglas L. Wheeler . 2014.