Ancient Greek dialects exhibit a great deal of geographic, diachronic, and sociolinguistic variation in their usage, both as spoken and as literary varieties. The Hellenistic age (4th – 1st cc. BC) was a crucial period for language contact and the rise of linguistic awareness, on account of the spread of a new variety used as lingua franca, the Koine. Previous studies have focussed on the diachronic spread of Koine and the gradual disappearance of the other Greek dialects, but still little is known on the linguistic and social factors of dialectal contact between them, and on the processes that led to the disappearance of dialects. My research will fill this gap by investigating dialectal mixture in inscriptions and the communicative situations involved. I will study Doric dialects—the variety most resilient to Koine— through a comparative analysis of different regions, to pinpoint the linguistic and sociolinguistic variables that led to language change, both locally and cross-dialectally. My methodology will consist of the examination of ancient sources through the lens of variationist sociolinguistics and in the application of theories of language contact and sociolinguistic variation to a corpus language such as Ancient Greek. The results will offer new insights into the history of the Greek language, the status of its varieties and the speakers’ perceptions of the language.