Since mid-nineteenth century, many Arabists and historians have referred to al-Andalus as a Muslim Spain. In the last decades, several scholars have criticized this historiographic tradition, which they see as a Hispanization of al-Andalus resulting from late-nineteenth-century nationalism. Although partly accurate, this criticism has overshadowed the fact that the success of the phrase Muslim Spain was not so much due to a Hispanization as to a de-Arabization of al-Andalus. Prior to the nineteenth century, Hispanizing al-Andalus was already a common historiographical practice: referring to the influence of the Iberian climate was enough to turn Arabs into Spaniards. The novelty of the last half of the nineteenth century was the triumph of racialism: national humors, until then attributed to geographical conditions, came to be understood as a product of biological inheritance. Thus, in order to continue Hispanizing al-Andalus, it was necessary to demonstrate (with the help of scientific anti-Semitism) that its inhabitants were not of Arabian race. And so Arab Spain became Muslim Spain.