speaking Tajik population of Central Asia, due to the fact that the Arab-Islamic army which invaded Central Asia also included some Persians who later governed the region like the Samanids. Persian was rooted into Central Asia by the Samanids. Classification Eastern Iranian remains in large part a dialect continuum subject to common innovation. Traditional branches, such as "Northeastern", as well as Eastern Iranian itself, are better considered language areas rather than genetic groups. The languages are as follows: Old Iranian period Northeast: Scythian, Old Saka,† etc. Central Iranian: Avestan† (c. 1000 – 7th century BC) Avestan is sometimes classified as Eastern Iranian, but is not assigned to a branch in recent classifications. Middle Iranian period Bactrian†, c. 4th century BC – 9th century AD Khwarezmian† (Chorasmian) c. 4th century BC – 13th century AD Sogdian†, from c. the 4th century AD Scytho-Khotanese (Saka)† (c. 5th century – 10th century AD) and Tumshuqese† (formerly Maralbashi, 7th century AD) Scytho-Sarmatian†, from c. the 8th century BC Modern languages (Neo-Iranian) Pashto (dialects: Northern, Southern, Central, and others) Wanetsi Pamir languages North Pamir Old Wanji (Vanji)† Yazgulami Shughni Shughni proper Oroshori Roshani Khufi Bartangi Sarikoli Sanglechi-Ishkashimi Sanglechi Ishkashimi Zebaki Wakhi Munji-Yidgha Munji Yidgha Ormuri-Parachi Ormuri Parachi Northern Yaghnobi Ossetian (dialects: Iron, Digor, Jassic†) Characteristics The Eastern Iranian area has been affected by widespread sound changes, e.g. t͡ʃ > ts. The initial syllable was in this word lost entirely in Yaghnobi due to a stress shift. Lenition of voiced stops Common to most Eastern Iranian languages is a particularly widespread lenition of the voiced stops *b, *d, *g. Between vowels, these have been lenited also in most Western Iranian languages, but in Eastern Iranian, spirantization also generally occurs in the word-initial position. This phenomenon is however not apparent in Avestan, and remains absent from Ormuri-Parachi. A series of spirant consonants can be assumed to have been the first stage: *b > *β, *d > *ð, *g > *ɣ. The voiced velar fricative has mostly been preserved. The labial member has been well-preserved too, but in most languages has shifted from a voiced bilabial fricative to the voiced labiodental fricative . The dental member has proved the most unstable: while a voiced dental fricative is preserved in some Pamir languages, it has in e.g. Pashto and Munji lenited further to . On the other hand, in Yaghnobi and Ossetian, the development appears to have been reversed,