JeL (Jaungoikoa eta Lagi-zaŕa, "God and the old law" in Basque, Lege-zaharra in Standard Basque) is the motto of the party. The "old laws" referred to are the fueros, the traditional laws of the Basque provinces, observed by the kings of Castille, and later Spain, until the Carlist Wars. The motto of Basque Carlists was Dios, patria, fueros, rey ("God, Country, Fueros, king"). Separatist nationalism in parts of Spain is related in some of these areas with former Carlist background.
JEL is the origin of jelkide ("JEL-companion", EAJ-PNV member) and jeltzale ("TZALE-follower", as in the gloss of EAJ, Eusko Alderdi Jeltzalea).
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