The Median language
 
Group Iranian (with Kurdish, Talysh etc.), Northwest Iranian (with Parthian, Baluchi etc.)
Geography & History Median tribes inhabited northwestern Iran obviously since the early 1st millennium BC. In 672, Media is an independent kingdom which began to develop very quickly in the Middle East. After in 550 it was conquered by Persians, another Iranian stock, the language fell out of use. The only source of knowledge about Median is a number Median loanwords in the Old Persian language, and glosses recorded in the ancient Akkadian, Aramaic, Greek and other texts: numerous place and personal names, appellatives and tribe names. An attempt to reconstruct Median phonetics and morphology was made by M.Mayrhofer (Die Rekonstruktion des Medischen, 1968). 
Phonetics Median phonetics is studied much better than its morphology which remains practically unknown. Median sounds look much like Old Persian, except the relfex of the Indo-European palatal stops: IE *k' gave Iranian *s' which is seen as q in Old Persian and s in Median; IE *g' turns into Old Persian ð, but Median z (Old Pers. ðaraniya- vs. Median *zari- 'gold').
Morphology Though almost no morphological elements are known from Median, we can suppose it was a typical Old Iranian language with a complex system of nominal and verbal inflections, the same as Avestan and Old Persian.
Writing No writing
Close Contacts Persian, Scythian, Akkadian, Urartian and maybe other languages of the ancient Mesopotamia.
Picture Ruins of Persepolis
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