Tierra Comunera (, TC) was a Castilian nationalist political party in the Spanish historical region of Castile. It was modelled after the Basque and Catalan nationalist parties but did not advocate full independence for Castile, instead favoring cooperation or unification among what they called the five Castilian regions within Spain (Castile and León, Castile-La Mancha, Madrid, Cantabria and La Rioja). It considered itself a left-of-centre, social democratic and environmentalist party.