Early in this period, which culminated in the creation of the Gupta Empire, relations with ancient Greece and Rome were not infrequent. The appearance of similar fundamental institutions of international law in various parts of the world show that they are inherent in international society, irrespective of culture and tradition. Inter-State relations in the pre-Islamic period resulted in clear-cut rules of warfare of a high humanitarian standard, in rules of neutrality, of treaty law, of customary law embodied in religious charters, in exchange of embassies of a temporary or semi-permanent character.Viswanatha, S.T., International Law in Ancient India, 1925
