Federalism from the Bottom: The Role of Basque Country and Catalonia in Shaping Federalism in Spain

The purpose of this chapter is to demonstrate that Spain represents a unique federal model shaped from the bottom, especially by the Basque Country and Catalonia. It examines how peculiar constitutional asymmetries—historical rights (derechos forales) and hechos diferenciales—have shaped the Spanish territorial Constitution since 1978, contributing to its federalising process. By discussing the latest academic scholarship on federal theory, this chapter examines the interplay between sovereignty, legal pluralism and sub-national autonomy. To this end, the federal jurisprudence of the Constitutional Tribunal will be recalled, as well as the recent developments under Sánchez, whose concessions—especially the 2024 Amnesty Act—have temporarily mitigated the Catalan crisis. Lastly, this chapter argues that Spain requires the constitutional recognition of its multinational reality as well as the entrenchment of asymmetry, preventing regression into homogenisation while preserving unity within diversity.