Abstract:The article explores how ancient Indian culture absorbed multiple foreign groups such as Greeks, Shakas, Kushans, and Huns. Despite their initial invasions, many of these groups gradually adopted Indian religious and cultural practices. Indian religions—particularly Buddhism, Shaivism, and Vaishnavism—offered logical, philosophical, and inclusive traditions that appealed to foreigners, especially those from tribal or proto-religious backgrounds. However, from the medieval period onward, such integration declined due to the increasing ritualism in Indian religions and the rise of Islam and Christianity, which discouraged conversion and promoted exclusivity. The article emphasises the early flexibility and philosophical depth of Indian thought, which allowed mutual cultural assimilation. Over time, with growing rigidity and complexity, Indian religious systems lost their appeal to outsiders, ending a rich phase of cultural and religious integration by the medieval era.

Keywords – Nasadiya Sukta, polytheism, henotheism, pantheism, monotheism.