Christianity is the predominant religion in Europe. Christianity has been practiced in Europe since the first century, and a number of the Pauline Epistles were addressed to Christians living in Greece, as well as other parts of the Roman Empire.
According to a 2010 study by the Pew Research Center, 76.2% of the European population identified themselves as Christians.
The word "Saracen" (/ˈsærəsən/ SARR-ə-sən) was commonly used in medieval Europe to refer to a person who lived in or near what the ancient Romans knew as Arabia Petraea and Arabia Deserta. Its original meaning in Greek and Latin is not known with certainty. By the early medieval period, it had come to be associated with the Arabian tribes. Following the rise of Islam, which occurred in Arabia, the word's definition evolved to refer not only to Arabs, but to Muslims as well. It eventually became the standard adjective among European Christians for all people and things from the Muslim world, regardless of whether they were Arab in origin.
The oldest known source mentioning "Saracens" in association with Muslims is the Greek-language Christian tract Doctrina Jacobi, which was compiled in the Byzantine Empire amidst the Muslim conquest of the Levant. The word became particularly widespread in European societies during the Crusades, when it was used by the Roman Catholic Church and by several European Christian political and military figures.