Spain's system of political parties was complicated by the existence of regional parties that were active both at the regional level, and, when they had seats in the Cortes, at the national level (see table 14, Appendix). In most autonomous communities, politics was dominated by regional affiliates of one of the two national parties, the PSOE and the AP, with the PSOE controlling the greater number of regions. In some of the autonomous communities, however, these regional offshoots had to form coalitions with truly local parties if they wished to govern. Only the Basque Country and Catalonia had regional parties that were strong enough to set the political agenda the most important were the PNV and the Catalan electoral coalition Convergence and Union (Convergència i Unio--CiU). These two moderately right-wing parties routinely won seats in the Cortes, and the CiU did well enough in regional elections to govern Catalonia, if it chose, without the aid of coalition partners. It was also the only regional party that had a decisive role in politics on the national level. This foremost exponent of Catalan nationalism occasionally supplied important parliamentary support to the UCD in the late 1970s. By far the second most important party in Catalonia was the regional offshoot of the PSOE, the Socialists' Party of Catalonia (Partit dels Socialistes de Catalunya--PSC).

The Catalan party system in general was characterized by pragmatism and by moderation. By contrast, the Basque national parties were beset by polarization, fragmentation, and political violence. In 1986 a group of PNV dissidents, unhappy with both the party's economic conservatism and its willingness to cooperate with the PSOE's stern antiterrorist measures, split from the party to form the more radical organization named Basque Solidarity (Eusko Alkartasuna--EA). In addition, there were two more extreme Basque nationalist groups, the Basque Left (Euskadiko Ezkerra--EE) and the HB. The more radical of these was the HB, which included Marxist-Leninist revolutionary and ultranationalist groups and which was closely linked to the ETAM . The party emphasized social revolution and armed struggle for Basque independence. The EE party was believed to be tied to the less violent ETA Political-Military Front (ETA Politico-Militar-- ETA-PM) (see Threats to Internal Security , ch. 5). These nationalist parties almost invariably won seats in the Cortes.

Data as of December 1988