Avestan
Spoken language
Avestan is an umbrella term for two Old Iranian languages, Old Avestan and Younger Avestan. They are known only from their conjoined use as the scriptural language of Zoroastrianism; the Avesta serves as their namesake. Wikipedia
Language families: Indo-European languages, Iranian languages, and Indo-Iranian languages
Era: Late Bronze Age, Iron Age
Writing system: Avestan alphabet; Gujarati script and Devanagari script (used by Indian Zoroastrians)