The Istanbul Greek (IG) community is an indigenous minority group totaling ~2000 members. Due to their specific geopolitical and sociohistorical context, the IG dialect has unique contact-induced linguistic features from Turkish, French, and other languages, in addition to archaisms and innovations. Because the IG community encompasses multilingual individuals who are ethnically Greek but nationally Turkish, they provide a unique opportunity to observe how identity is represented and circulated with language. This dissertation presents an ethnographic and variationist sociolinguistic analysis of the IG community and their speech. Six months of ethnographic observation over 2016 and 2018 resulted in interviews with over 80 IG speakers of various demographic backgrounds. Sociolinguistic interviews elicited a range of dialectal variants from a range of task types. I acoustically measured phonetic features of IG that differ from Standard Modern Greek (SMG) from wordlist data and ran mixed-effects models along conventional linguistic and social factors. The results from these analyses show that a salient dialectal feature (velarized laterals) patterns as expected with traditional variationist research, but only with young females. Meanwhile a less salient dialectal feature (postalveolar affricates) does not pattern as expected regardless of demographics. Factors such as social networks and language ideologies do not reliably account for how these and other variables pattern. These results are triangulated with metapragmatic commentary of IG speakers discussing their language. Metapragmatic discourse reveals specific social meaning attributed to these dialectal features and to IG holistically. Speakers appeal to chronotopic relationships with their language use and IG identity, which represents cosmopolitanism and urban sophistication that contrasts with SMG. IG speakers' awareness of dialectal differences and qualities associated with such differences are then used to form characterological figures that reinforce an IG identity in opposition with SMG. Laterals serve as an index of IG identity for all IGs, whereas postalveolar affricates do not have the same social meaning, which aligns with how these features pattern in the community. As a result, the variation seen in IG cannot be explained by traditional methods alone. Knowledge of the specific IG sociohistorical context is important because social meaning is crucially what drives language change.