There has been much discussion respecting the relation of Chen-la to the older kingdom of Fu-nan which is the name given by Chinese historians until the early part of the seventh century to a state occupying the south-eastern and perhaps central portions of Indo-China.  It has been argued that Chen-la is simply the older name of Fu-nan and on the other hand that Fu-nan is a wider designation including several states, one of which, Chen-la or Camboja, became paramount at the expense of the others.[246] But the point seems unimportant for their religious history with which we have to deal.  In religion and general civilization both were subject to Indian influence and it is not recorded that the political circumstances which turned Fu-nan into Chen-la were attended by any religious revolution.

The most important fact in the history of these countries, as in Champa and Java, is the presence from early times of Indian influence as a result of commerce, colonization, or conquest.  Orientalists have only recently freed themselves from the idea that the ancient Hindus, and especially their religion, were restricted to the limits of India.  In mediaeval times this was true.  Emigration was rare and it was only in the nineteenth century that the travelling Hindu became a familiar and in some British colonies not very welcome visitor.  Even now Hindus of the higher caste evade rather than deny the rule which forbids them to cross the ocean.[247] But for a long while Hindus have frequented the coast of East Africa[248] and in earlier centuries their traders, soldiers and missionaries covered considerable distances by sea.  The Jatakas[249] mention voyages to Babylon:  Vijaya and Mahinda reached Ceylon in the fifth and third centuries B.C. respectively.  There is no certain evidence as to the epoch when Hindus first penetrated beyond the Malay peninsula, but Java is mentioned in the Ramayana:[250] the earliest Sanskrit inscriptions of Champa date from our third or perhaps second century, and the Chinese Annals of the Tsin indicate that at a period considerably anterior to that dynasty there were Hindus in Fu-nan.[251] It is therefore safe to conclude that they must have reached these regions about the beginning of the Christian era and, should any evidence be forthcoming, there is no reason why this date should not be put further back.  At present we can only say that the establishment of Hindu kingdoms probably implies earlier visits of Hindu traders and that voyages to the south coast of Indo-China and the Archipelago were probably preceded by settlements on the Isthmus of Kra, for instance at Ligor.