The Mamluk Sultanate was an Islamic regime that ruled over Egypt and Syria from 1250 to 1517. While the population at large was Arab and spoke Arabic, its ruling elite was not: imported as military slaves or mamluks from their Central Asia, these were Turkic or Circassian by language and ethnicity. Having changed their nomadic homeland for a settled life in an Arabo-Islamic environment, this elite was commonly believed to have shed its ethnic and linguistic antecedents and to have replaced these with a new identity constructed solely around mamluk-dom. More conventional categories such as ethnicity and blood ties were considered no longer relevant, be it for in-group identification, outward legitimation or social networking. However, scholars increasingly start questioning this prevalent view. Mamluk identity is now rethought as a complex construct, in which mamluk-dom is but one dimension. As it appears that the Mamluks’ most favoured self-designation throughout their history was an ethnic/linguistic one (‘Regime of the Turks’, not ‘Regime of the Mamluks’), it is clear that ethnicity and language constitute another crucial dimension. What the project aims at is establishing how these dimensions were constructed and what they were to communicate, in short, clarifying what it meant to be a Turk or a Circassian in the Sultanate. What it needs is an approach that integrates both its Turkic and its Arabic sources, and combines a historical and a sociolinguistic perspective.