The oldest known source mentioning “Saracens” in relation to Islam dates back to the 7th century, in the Greek-language Christian tract Doctrina Jacobi. Among other major events, the tract discusses the Muslim conquest of the Levant, which occurred after the rise of the Rashidun Caliphate following the death of the Islamic prophet Muhammad.[5] The Roman Catholic Church and European Christian leaders used the term during the Middle Ages to refer to Muslims—usually Arabs, Turks, and Iranians.

Saracens were founded in 1876 by the Old Boys of the Philological School in Marylebone, London (later to become St Marylebone Grammar School ). The club’s name is said to come from the “endurance, enthusiasm and perceived invincibility of Saladin ‘s desert warriors of the 12th century “.
In 1493 Alexander VI issued the bull Inter Caetera stating one Christian nation did not have the right to establish dominion over lands previously dominated by another Christian nation, thus establishing the Law of Nations. Together, the Dum Diversas, the Romanus Pontifex, and the Inter Caetera came to serve as the basis and justification for the Doctrine of Discovery, the global slave trade of the 15th and 16th centuries, and the Age of Imperialism.
Pope Nicholas V issued the papal bull Dum Diversas on 18 June 1452. It authorized Alfonso V of Portugal to reduce any “Saracens (Muslims) and pagans and any other unbelievers” to perpetual slavery. This facilitated the Portuguese slave trade from West Africa, it extended to the Catholic nations of Europe dominion over discovered lands during the Age of Discovery. Along with sanctifying the seizure of non-Christian lands, it encouraged the enslavement of native, non-Christian peoples in Africa and the New World.