The Ptolemy world map is a map of the world known to the Roman Empire in the 2nd c. AD. It is based on the description contained in Ptolemy’s book Geography, written c. 150.
Ptolemy’s work probably originally came with maps, but none have been discovered. Instead, the present form of the map was reconstructed from Ptolemy’s coordinates by Byzantine monks under the direction of Maximus Planudes shortly after 1295. It probably was not that of the original text, as it uses the less favoured of the two alternate projections offered by Ptolemy.
The continents are given as Europe, Asia, and Libya (Africa). The World Ocean is only seen to the west. The map distinguishes two large enclosed seas: the Mediterranean and the Indian (Indicum Pelagus). Due to Marinus and Ptolemy’s mistaken measure of the circumference of the earth, the former is made to extend much too far in terms of degrees of arc; due to their reliance on Hipparchus, they mistakenly enclose the latter with an eastern and southern shore of unknown lands, which prevents the map from identifying the western coast of the World Ocean.
India is bound by the Ganges Rivers, but it’s peninsula is much shortened. The nation of Scythia located on the Indus River Valley is coterminous to Pakistan. Ceylon (Taprobane) is greatly enlarged due to its reputation. The Malay Peninsula is given as the Golden Chersonese instead of the earlier “Golden Island”, which derived from Indian accounts of the mines on Sumatra. Beyond the Golden Chersonese, the Great Gulf (Magnus Sinus) forms a combination of the Gulf of Thailand and South China Sea which is bound by the unknown lands thought to enclose the Indian Sea. China is divided into two realms—the Qin (Sinae) and the Land of Silk (Serica)—owing to the different accounts received from the overland and maritime Silk Roads.
The Geography and the map derived from it probably played an important role in the expansion of the Roman Empire to the East. Trade throughout the Indian Ocean was extensive from the 2nd c. AD, and many Roman trading ports have been identified in India. From these ports, Roman embassies to China are recorded in Chinese historical sources from around 166 AD.