Aksum
The highlands of Ethiopia and Eritrea, Aksum's rise in the 1st century CE, the Periplus and Red Sea trade, coinage from about 270 CE, royal stelae and tombs, King Ezana and conversion to Christianity, Ge'ez script, Aksum and Arabia (Himyar), the return of the Aksum obelisk in 2005, decline, and the Zagwe and Solomonic successors (Lalibela).
A great power of late antiquity
Aksum's coins, inscriptions in Ge'ez, Greek and Sabaean, and stelae make it one of the best-documented ancient African states. In the 6th century Aksum intervened militarily in southern Arabia (Himyar). The Ethiopian tradition that the Ark of the Covenant rests in Aksum, and the Solomonic dynasty's claim of descent from Solomon and the Queen of Sheba (recorded in the 14th-century Kebra Nagast), are part of national tradition rather than historical evidence.
Stuart Munro-Hay, Aksum: An African Civilisation of Late Antiquity (1991); David Phillipson, Foundations of an African Civilisation: Aksum and the Northern Horn (2012); The Periplus of the Erythraean Sea (1st century CE, trans. Lionel Casson, 1989).