Spanish unionism is a label used by Basque and Catalan independence movements to refer to the political attitude which favours the continuity of the Kingdom of Spain as a single united nation-state.
Namely, the expression Spanish unionism has been used only for the last 10 years in the context of the Catalan independentist debate. Prior to this, usage of the term was limited to Basque nationalism.
The importation of the term unionism into the Spanish context and its usage with pejorative meaning is related to the peripheral nationalism attempts to introduce the terminology of the Northern Ireland conflict in the Basque conflict and the Catalonian independence debate.
In this way, Spanish unionism is considered by Basque and Catalonian nationalist parties as a political ideology identified by its denial of the exercise of the right of self-determination of the peripheral nationalities of Spain or sometimes by the simple defense of Spain as a nation. Therefore, the label has been applied to parties such as the People's Party, Spanish Socialist Workers Party (PSOE) (however sometimes PSOE is seen as more sympathetic to Spain's nationalist movements), Union, Progress and Democracy (UPYD) and Citizens-Party of the Citizenry (C's).