When were Arabic numerals introduced to Europe?
Arabic numerals
The reason the digits are more commonly known as "Arabic numerals" in Europe and the Americas is that they were introduced to Europe in the 10th century by Arabic-speakers of North Africa, who were then using the digits from Libya to Morocco. Arabs, on the other hand, call the base-10 system (not just these digits) "Hindu numerals", referring to their origin in India. This is not to be confused with what the Arabs call the "Hindi numerals", namely the Eastern Arabic numerals ( - - - - - - - - - ) used in the Middle East, or any of the numerals currently used in Indian languages (e.g. Devanagari: ).
Arabs in Europe
The Iberian Peninsula was mapped as "Al-Andalus" by the new Muslim invaders. The Arabs, as well as the overall Muslim populations (a mix of Berbers and Arabs) of Al-Andalus and North Africa, were referred to as "Moors". Spain enjoyed a golden era of Islamic culture, accompanied by a golden age of Sephardic Jewish culture. This era spawned great Arabic polymaths and intellectuals such as Averroes and Albucasis. The Islamic rule in Spain also saw the birth of the Aljamiado alphabet, an Arabic alphabet for the Spanish language. In the 15th century, the Muslims were defeated by the Christian armies in a historical process called Reconquista (meaning reconquest in Spanish and Portuguese), which led the Christian monarchs to regain control over the Hiberian peninsula. Much of the architecture that was concocted from this era remains intact in Spain and functions as famous tourist destinations since the Catholic monarchs decided to use them rather than destroy them.