Is there any reason to assume Persian language would have been less influential in an India invaded by Central Asians who hadn't converted to Islam?Totally and utterly different. Every North Indian language has been extremely affected by Persian - Hindustani, for instance, was originally a creole between Persian and the language of Delhi that spread across North India to act as something of a lingua franca in North India, as well as the Deccan Plateau, and became a prestigious language as a result.