High Quality Content by WIKIPEDIA articles! Spanish nationality law refers to all the laws of Spain concerning nationality. The 11th article of the First Title of the Spanish Constitution refers to Spanish nationality and establishes that a separate law is to regulate how it is acquired and lost. This separate law is the Spanish Civil Code. In general terms, Spanish nationality is based on the principle of jus sanguinis, even though certain limited provisions exist for the acquisition of Spanish nationality based on the principle of jus soli.