Source: TW
I don’t think most Indians realize how significant Xuánzàng’s account is. Our earliest firsthand foreign traveler account of India comes from Megasthenes, who was likely a Seleucid ambassador sent to the Mauryan court of Chandragupta Maurya. Prior accounts are not as reliable. Ctesias’ account is largely fictional, Herodotus’ accounts is largely hearsay from Persians and other intermediaries. While Strabo, Arrian, Pliny the Elder, and Ptolemy are a bit more reliable, none of them personally visited India.
Unfortunately, Megasthenes’ Indica is fragmentary and only known from fragments from other texts.
Our second earliest firsthand traveler account is the Periplus of the Erythrean Sea, but it’s primarily a merchant’s maritime guide focused on ports and trade rather than a detailed narrative account of India itself.
Our third earliest traveler account is of the Buddhist monk Fǎxiǎn. This is the oldest complete and extant travel diary of India written by a foreign visitor, but it’s very short. Only around 100 pages.
Our fourth oldest account is that of Cosmas Indicopleustes, an Alexandrian merchant who sought to disprove “pagan” science and establish that the Earth was shaped like a tabernacle based on his reading of the Bible. This tabernacle view was unique even among contemporary Christians.
Most Christians during his time believed that the earth was either a sphere or flat. Even Augustine was open to the view of a spherical earth, though he believed that no one lived in the Southern hemisphere as there was no way a person could get to the other side through the torrid equatorial zone.
Xuánzàng’s Great Táng Records on the Western Regions is our first substantial firsthand foreign account of India.
Aside from epigraphy, Xuánzàng’s was Alexander Cunningham’s main source for locating lost sites like Nālandā and Sārnāth. Francis Buchanan had noted the mounds at Nālandā, but it was Xuánzàng’s descriptions of the university’s layout and surrounding landmarks that allowed Cunningham to definitively recognize & survey the site in the 1860s.