Eudoxus of Cyzicus

Eudoxus of Cyzicus (/ˈjuːdəksəs/; Greek: Εὔδοξος, Eúdoxos; fl. c. 130 BC) was a Greek navigator who explored the Arabian Sea for Ptolemy VIII, king of the Hellenistic Ptolemaic dynasty in Egypt.

According to Poseidonius, later reported in Strabo's Geography, the monsoon wind system of the Indian Ocean was first sailed by Eudoxus of Cyzicus in 118 or 116 BC. Poseidonius said a shipwrecked sailor from India had been rescued in the Red Sea and taken to Ptolemy VIII in Alexandria. The unnamed Indian offered to guide Greek navigators to India. Ptolemy appointed Eudoxus of Cyzicus, who made two voyages from Egypt to India. The first, in 118 BC, was guided by the Indian sailor. After Eudoxus returned with a cargo of aromatics and precious stones a second voyage was undertaken in 116 BC. Eudoxus navigated the second voyage, sailing without a guide.

Strabo, whose Geography is the main surviving source of the story, was skeptical about its truth. Modern scholarship tends to consider it relatively credible. During the 2nd century BC Greek and Indian ships met to trade at Arabian ports such as Aden (called Eudaemon by the Greeks). Attempts to sail beyond Aden were rare, discouraged, and involved a long and laborious coast-hugging journey. Navigators had long been aware of the monsoon winds. Indian ships used them to sail to Arabia, but no Greek ship had yet done so. For the Greeks to acquire the expertise of an Indian pilot meant the chance to bypass the Arabian ports and establish direct commercial links with India. Whether or not the story told by Poseidonius of a shipwrecked Indian pilot teaching Eudoxus about the monsoon winds is true, Greek ships were in fact soon using the monsoon winds to sail to India. By 50 BC there was a marked increase in the number of Greek and Roman ships sailing the Red Sea to the Indian Ocean.

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