In the 5th century BC, Darius the Great of the Achaemenid dynasty called the Persian Gulf “Draya; tya; haca; parsa: Aitiy”, meaning, “The sea which goes from Persian.” In this era, some of the Greek writers also called it “Persikonkaitas”, meaning the Persian Gulf. Claudius Ptolemaues, the celebrated Greco-Egyptian mathematician/astronomer in the 2nd century called it “Persicus Sinus” or Persian Gulf. In the 1st century AD, Quintus Curtius Rufus, the Roman historian, designated it “Aquarius Persico” – the Persian Sea. Flavius Arrianus, another Greek historian, called it “Persiconkaitas” (Persian Gulf).