Visigothic Hispania, Islamicate al-Andalus and Christian Spain are names representing three scriptural monotheistic civilizations in Iberia. Al-Andalus has stood apart from this list by representing a time and a place of convivencia in which Christians, Jews and Muslims cooperated and coexisted. Why and how the Islamicate civilization in al-Andalus differed from the Visigoths or the Spanish, despite all three sharing a religious orientation is an historical puzzle. By exploring the legal status of Jews within the legal regimes of Christian Rome and Visigothic Hispania, this thesis will suggest that it is cosmopolitanism and its converse exclusivism that best explain concepts of convivencia or coexistence in the face of religious diversity.