Why was Spain and Sicily the major areas of Islamic influence in Europe?

While Spain was indeed a major area of Islamic influence in Europe, Sicily was actually not. Sicily briefly came under Islamic rule in the 10th century, but it was reconquered by the Normans in the 11th century and quickly became a center of Christian culture. Instead, it is southern Italy that was the other major area of Islamic influence in Europe, as it remained under Muslim control from the 9th to the 11th centuries.