Horn of Africa Himyarite Kingdom. Under Ezana (fl. 320–360), the kingdom of Aksum became the first major empire to adopt Christianity, and was named by Mani as one of the four great powers of his time, along with Persia, Rome and China. Northern Somalia was an important link in the Horn, connecting the region's commerce with the rest of the ancient world. Somali sailors and merchants were the main suppliers of frankincense, myrrh and spices, all of which were valuable luxuries to the Ancient Egyptians, Phoenicians, Mycenaeans, Babylonians and Romans. The Romans consequently began to refer to the region as "Regio Aromatica". In
Languages of Africa expansion, in which Bantu-speaking peoples expanded over most of Sub-Equatorial Africa, displacing Khoi-San speaking peoples from much of Southeast Africa and Southern Africa and other peoples from Central Africa. Another example is the Arab expansion in the 7th century, which led to the extension of Arabic from its homeland in Asia, into much of North Africa and the Horn of Africa. Trade languages are another age-old phenomenon in the African linguistic landscape. Cultural and linguistic innovations spread along trade routes and languages of peoples dominant in trade developed into languages of wider communication (lingua franca). Of particular importance in this