The Sogeram languages are a family of ten languages spoken in central Madang Province, Papua New Guinea. This dissertation presents a reconstruction of Proto-Sogeram, including sections on its phonology, lexicon, verbal morphology, nominal morphology, and syntax. The methodology employed is, for the most part, the traditional comparative method, especially in the sections focusing on phonology, lexicon, and morphology. But I also argue for methodological innovations to the comparative method, which are grounded in a theoretical understanding of the nature of language and language change. These innovations allow for the reconstruction of syntax, and I reconstruct a good deal of the grammar of Proto-Sogeram. I also discuss many of the various innovations that the Sogeram languages have undergone, and conclude with a grammar sketch of Proto-Sogeram as I reconstruct it.

The dissertation also contains six appendices, each of which is a grammar sketch of a previously undescribed Sogeram language. (Appendix 4 is actually a description of the two closely related Aisi languages.) These are the result of my fieldwork in Madang Province. The data from that fieldwork, along with data from other linguists on the three other Sogeram languages, constitutes the synchronic material on which the reconstruction is based.