A diachronic study of the impersonal passive in Ainu

This paper provides a diachronic account for the impersonal passive in Ainu which is marked with a(n)= in Saru (Southwestern Hokkaido) and with a(n)= for 3sg/pl.o and ci= for 1sg/pl.o in Ishikari (Northeastern Hokkaido). I have argued that in spite of clearly impersonal origins, neither the a(n)= -marked nor the ci= -marked construction can be regarded as impersonal because of the possibility of the inclusion of an oblique actor phrase and that none of the constructions can be regarded as personal passive because reanalysis of O to S is incomplete: only some topic-related subject properties (word order etc.) have been acquired by O but no single agent-related subject property has been acquired yet. In the context of the discussion of grammaticalization pathway IMPERSONAL > IMPERSONAL PASSIVE > PASSIVE, of special interest is the action nominalization origin of the a(n)= -marked construction. Keywords: Ainu; Saru; Ishikari; impersonal passive; grammaticalization; action nominalization