...Less than seventy years after the death of Mohammed in 632, his followers had already conquered most of the Middle East and North Africa. In the beginning of the eighth century, the leaders of the new religion turned their eyes to Christian Europe, dreaming of new Moorish conquests. On the other side of the Strait of Gibraltar, Visigoth Catholic Spain was in a state of decadence, undermined by the Arian heresy, steeped in vice, its army and people lax, and its leaders divided. In 711, because of internal divisions, traitors informed the Muslims about the weak points along the Spanish...