Huntingford has identified with the Dahlak archipelago a group of islands near Adulis called "Alalaiou" in the Periplus of the Erythraean Sea which were a source of tortoise shell.

According to Edward Ullendorff, the Dahlak islanders were amongst the first people in the Horn of Africa to embrace Islam, and a number of tombstones in Kufic script attest to this early connection.

Sultan Ahmad joined the Adal Empire and was rewarded with the port town of Arkiko, which before the war had belonged to Medri Bahri.

Other islands of the archipelago are Dhuladhiya, Dissei, Dohul (Dehil), Erwa, Harat, Harmil, Isra-Tu, Nahaleg, Nakura, Nora (Norah) and Shumma.

Residents of the archipelago speak Dahlik and maintain a traditional way of life, including fishing, shepherding and raising camels.