This dissertation reconstructs the history of the Flores-Lembata languages (Austronesian, eastern Indonesia) by investigating traces of contact in the lexicon as well as grammar. Part I fills a gap in the documentation of the Flores-Lembata languages by providing a descriptive grammar of the Central Lembata language, as representative of the previously undescribed central group of Lamaholot varieties. Part II researches the history of the phonology and the lexicon of the Flores-Lembata languages and provides evidence for both inherited lexical items and a non-Austronesian lexical substrate. Part III examines morpho-syntactic features and their history of contact. Eight structural features of the Flores-Lembata languages which are atypical for Austronesian languages are described and evaluated on their potential of being the result of contact with non-Austronesian languages of the area.

Combining this lexical and typological evidence, it is proposed that the Flores-Lembata languages have been in contact with one or more languages typologically similar to the non-Austronesian Alor-Pantar languages that are currently spoken on two adjacent islands to the east of the Lamaholot area. This contact between Flores-Lembata languages and non-Austronesian languages of the Alor-Pantar type must have been ongoing since the time of Proto-Flores-Lembata until after the break-up of the family into subgroups. Some subgroups have gained more non-Austronesian features than others. This suggests that the contact of each of the subgroups with non-Austronesian language(s) must have varied in intensity and length.