The earliest attested Sanskrit texts are Brahmanical texts of the Rigveda, from the mid-to-late second millennium BCE. No written records from such an early period survive, if they ever existed. However, scholars are confident that the oral transmission of the texts is reliable: they were ceremonial literature whose correct pronunciation was considered crucial to its religious efficacy.

From the Rigveda until the time of Pāṇini (fourth century B.C.E.) the development of the early Vedic language can be observed in other Vedic texts: the Samaveda, Yajurveda, Atharvaveda, Brahmanas, and Upanishads. During this time, the prestige of the language, its use for sacred purposes, and the importance attached to its correct enunciation all served as powerful conservative forces resisting the normal processes of linguistic change. However, there is a clear, five-level linguistic development of Vedic from the Rigveda to the language of the Upanishads and the earliest Sutras (such as Baudhayana).