Between the seventh and eleventh centuries, Christian worship on the Iberian Peninsula was structured by rituals of great theological and musical richness, known as the Old Hispanic (or Mozarabic) rite. Much of this liturgy was produced during a seventh-century cultural and educational program aimed at creating a society unified in the Nicene faith, built on twin pillars of church and kingdom. Led by Isidore of Seville and subsequent generations of...