13th century), and the Middle Persian of the Church of the East, evidenced in the Pahlavi Psalter (7th century); these were used until the beginning of the second millennium in many places in Central Asia, including Turpan and even localities in South India. All three differ minimally from one another and indeed the less ambiguous and archaizing scripts of the latter two have helped to elucidate some aspects of the Sasanian-era pronunciation of the former. Phonology Vowels The vowels of Middle Persian were the following: It has been doubted whether the Middle Persian short mid vowels /e/ and /o/ were phonemic, since they do not appear to have a unique continuation in later forms of Persian and no minimal pairs have been found. The evidence for them is variation between spelling with and without the matres lectionis y and w, as well as etymological considerations. They are thought to have arisen from earlier /a/ in certain conditions, including, for /e/, the presence of a following /n/, sibilant or front vowel in the next syllable, and for /o/, the presence of a following labial consonant or the vowel /u/ in the next syllable. Long /eː/ and /oː/ had appeared first in Middle Persian, since they had developed from the Old Persian diphthongs /ai/ and /aw/. Consonants The consonant phonemes were the following: A major distinction between the pronunciation of the early Middle Persian of the Arsacid period (until the 3rd century CE) and the Middle Persian of the Sassanid period (3rd – 7th century CE) is due to a process of consonant lenition after voiced sounds that took place during the transition between the two. Its effects were as follows: 1. Voiced stops, when occurring after vowels, became semivowels: /b/ > /w/, /d/ > /j/, /g/ > /w/ or /j/ (the latter after /i/) This process may have taken place very early, but it is nevertheless often the old pronunciation or a transitional one that is reflected in the Pahlavi spelling. Old Persian naiba- > Middle Persian nēw (Pahlavi TB or nyw'), but: Old Persian asabāra- > Middle Persian asvār 'horseman' (Pahlavi PLŠYA, ʾswblʾ). Proto-Iranian *pād- > Middle Persian pāy 'foot' (Pahlavi LGLE, pʾd, Manichaean pʾy). Old Persian magu- > Middle Persian mow- 'Magian' (Pahlavi mgw-). Proto-Iranian *ni-gauš- > Middle Persian niyōš- 'listen' (Pahlavi nydwhš-, also nydwk(h)š-), Manichaean nywš). 2. Voiceless stops and affricates, when occurring after vowels as well as