Early usage and origins
The Latin term Saraceni is of unknown original meaning. There are claims of it being derived from the Semitic triliteral root srq "to steal, rob, plunder", and perhaps more specifically from the noun sāriq (Arabic: سارق), pl. sariqīn (سارقين), which means "thief, marauders, plunderers". Other possible Semitic roots are šrq "east" and šrkt "tribe, confederation". In his Levantine Diary, covering the years 1699-1740, the Damascene writer
ibn Kanan (Arabic: محمد بن كَنّان الصالحي) used the term sarkan to mean "travel on a military mission" from the Near East to parts of Southern Europe which were under Ottoman Empire rule, particularly Cyprus and Rhodes.
Ptolemy's 2nd-century work, Geography, describes Sarakēnḗ (Ancient Greek: Σαρακηνή) as a region in the northern Sinai Peninsula. Ptolemy also mentions a people called the Sarakēnoí (Ancient Greek: οἱ Σαρακηνοί) living in the northwestern Arabian Peninsula (near neighbor to the Sinai). Eusebius in his Ecclesiastical history narrates an account wherein Pope Dionysius of Alexandria mentions Saracens in a letter while describing the persecution of Christians by the Roman emperor Decius: "Many were, in the Arabian mountain, enslaved by the barbarous 'sarkenoi'." The Augustan History also refers to an attack by Saraceni on Pescennius Niger's army in Egypt in 193, but provides little information as to identifying them.
Both Hippolytus of Rome and Uranius mention three distinct peoples in Arabia during the first half of the third century: the Taeni, the Saraceni, and the Arabes. The Taeni, later identified with the Arab people called Tayy, were located around Khaybar (an oasis north of Medina) and also in an area stretching up to the Euphrates. The Saraceni were placed north of them. These Saracens, located in the northern Hejaz, were described as people with a certain military ability who were opponents of the Roman Empire and who were classified by the Romans as barbarians.
The Saracens are described as forming the equites (heavy cavalry) from Phoenicia and Thamud. In one document the defeated enemies of Diocletian's campaign in the Syrian Desert are described as Saracens. Other 4th-century military reports make no mention of Arabs but refer to as Saracens groups ranging as far east as Mesopotamia that were involved in battles on both the Sasanian and Roman sides. The Saracens were named in the Roman administrative document Notitia Dignitatum—dating from the time of Theodosius I in the 4th century—as comprising distinctive units in the Roman army. They were distinguished in the document from Arabs.