Iberian Federalism

Iberian federalism, Pan-Iberism or simply Iberism (Spanish, Basque, Portuguese and Galician: Iberismo, Catalan: Iberisme) is a pan-nationalist ideology developed mainly during the beginning of the 20th century, supporting the federation into a single state of the two main countries on the Iberian Peninsula: Portugal and Spain.

These unification ideas were promoted mainly by minority republican and socialist movements in both nations. There was never any popular support in Andorra and Gibraltar in favour of joining such a project.

Portugal and Spain share a common history. Spanish and Portuguese are both Romance languages and have influenced each other and both countries have similar ethnicity and culture.

The Portuguese language began its independent evolution from the medieval Galician-Portuguese when the County of Portugal separated from the Kingdom of Galicia by becoming the Kingdom of Portugal. On the other hand, the Galician language has become increasingly influenced by the Castilian language since Galicia's incorporation into the Crown of Castile as a dependent Kingdom of León.

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