The Dahlak Archipelago is an Eritrean island group located in the Red Sea near Massawa, Eritrea. It consists of two large and 124 small islands. The pearl fisheries of the archipelago have been famous since Roman times and still produce a substantial number of pearls.
Only four of the islands are permanently inhabited, of which Dahlak Kebir is the largest and most populated. Other islands of the archipelago are Dhuladhiya, Dissei, Dohul (Dehil), Erwa, Harat, Harmil, Isra-Tu, Nahaleg, Nakura, Nora (Norah) and Shumma, although only Nora and Dohul are permanently inhabited, besides the main island. The islands are home to a diverse marine life and sea-birds, and attract an increasing number of tourists. Residents of the archipelago speak Dahlik, and maintain a traditional way of life including fishing and herding goats and camels. The islands can be reached by boat from Massawa and are popular with scuba divers and snorkellers.
G.W.B. 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.
In the 7th century, an independent state emerged in the archipelago. However, it was subsequently conquered by Yemen, then by the Ethiopian Empire. In 1517 the Ottoman Turks conquered the islands and placed them under the rule of the Pasha at Suakin as part of the province of Habesh. By 1526 the Dahalik sultan, Ahmad, had been degraded to a tributary. There was a short revival of the sultanate during the Abyssinian-Adal war, where the sultanate of Adal waged a temporarily successful jihad against the Ethiopian Empire. Sultan Ahmad joined the Somali Adal Empire and was rewarded with the port town of Arkiko, which before the war had belonged to Medri Bahri. However, in 1541, one year after the death of sultan Ahmad, the Portuguese returned and destroyed Dahlak yet again.