The Adal Sultanate, or the Adal Empire or the ʿAdal or the Bar Saʿad dīn (alt. spelling Adel Sultanate, Adal Sultanate) () was a medieval Sunni Muslim Empire which was located in the Horn of Africa. It was founded by Sabr ad-Din II after the fall of the Sultanate of Ifat. The kingdom flourished circa 1415 to 1577. The sultanate and state were established by the local inhabitants of Zeila. or the Harar plateau. At its height, the polity under Sultan Badlay controlled the territory stretching from Somaliland to the port city of Suakin in Sudan. The Adal Empire maintained a robust commercial and political relationship with the Ottoman Empire. Etymology Adal is believed to be an abbreviation of Havilah. Eidal or Aw Abdal, was the Emir of Harar in the eleventh century. In the thirteenth century, the Arab writer al-Dimashqi refers to the Adal Sultanate's capital, Zeila, by its Somali name "Awdal" (). The modern Awdal region of Somaliland, which was part of the Adal Sultanate, bears the kingdom's name. Locally the empire was known to the Muslims as Bar Sa'ad ad-din meaning "The country of Sa'ad ad-din" History Sultanate established Ethiopian historian Taddesse Tamrat states Adal's central authority in the fourteenth century consisted of the Argobba, Harari and Silt'e people. According to Patrick Gikes, Adal in the sixteenth century designated the ancient Harla and Somali people. Marriage alliances between Argobba, Harari and Somali people were also common within the Adal Sultanate. Kingdom established Adal Kingdom (also Awdal, Adl, or Adel) was centred around Zeila, its capital. It was established by the local Somali tribes in the early ninth century. Zeila attracted merchants from around the world, contributing to the wealth of the city. Zeila is an ancient city and it was one of the earliest cities in the world to embrace Islam. In the late ninth century, Al-Yaqubi, an Armenian Muslim scholar and traveller, wrote that the Kingdom of Adal was a small wealthy kingdom and that Zeila served as the headquarters for the kingdom, which dated back to the beginning of the century. Islamic influence Islam was introduced to the Horn region early on from the Arabian peninsula, shortly after the hijra. Zeila's two-mihrab Masjid al-Qiblatayn dates to about the seventh century, and is the oldest mosque in Africa. In the late ninth century, Al-Yaqubi wrote that Muslims were living along the northern Somali seaboard. The polity