Classification
Old Persian belongs to the Iranian language family which is a branch of the Indo-Iranian language family, and is sibling to another branch called Indo-Aryan languages. Indo-Iranian languages is itself within the large family of Indo-European languages. The common ancestors of Indo-Iranians came from Central Asia sometime in the first half of the 2nd millennium BCE. The extinct and unattested Median language is another Old Iranian language related to Old Persian (e.g. both are classified as Western Iranian languages and many Median names appeared in Old Persian texts) The group of Old Iranian languages was presumably a large group; however our knowledge of it is restricted mainly to Old Persian, Avestan and Median. The former are the only languages in that group which have left written original texts while Median is known mostly from loanwords in Old Persian.
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