Genesis 36 contains a distinctively large and heterogeneous body of genealogical materials pertaining to Esau and the kingdom of Edom. The present study suggests that the chapter reached its unique shape as the result of a specifically Judahite discursive project. In particular, a scribe expanded a preexisting priestly genealogy of Esau in order to create a robust boundary between entities defined as Edom and Israel. New interpretations of archaeological evidence from southern Jordan and the Negev reveal the context of dynamic interaction and fluid identities that likely prompted this expansion. The resulting text rejects memories of affiliation between Negevite and south Jordanian peoples in order to elevate Judah’s claim to the name and identity of Israel.