Empire

he Empire of Aksum at its height extended across most of present-day Eritrea, northern Ethiopia, Yemen, southern Saudi Arabia and northern Sudan. The capital city of the empire was Aksum, now in northern Ethiopia. Today a smaller community, the city of Aksum was once a bustling metropolis, cultural and economic center. Two hills and two streams lie on the east and west expanses of the city; perhaps providing the initial impetus for settling this area. Along the hills and plain outside the city, the Aksumites had cemeteries with elaborate grave stones called stelae, or obelisks. Other important cities included Yeha, Hawulti, Matara, Adulis, and Qohaito, the last three of which are now in Eritrea.
In the 3rd century, Aksum began interfering in South Arabian affairs, controlling at times the western Tihama region among other areas. It dominated states on the Arabian Peninsula across the Red Sea, making them pay Axum a regular tribute.^[7] By the late 3rd century it had begun minting its own currency and was named by Mani as one of the four great powers of his time along with Persia, Rome, and China. It converted to Christianity in 325 or 328 under King Ezana and was the first state ever to use the image of the cross on its coins. By 350, they conquered the Kingdom of Kush.^[7] At its height, Aksum controlled northern Ethiopia, Eritrea, northern Sudan, southern Egypt, Djibouti, Yemen, and southern Saudi Arabia, totalling 1.25 million km².^[8]
Aksum remained a strong empire and trading power until the rise of Islam in the 7th century. However, unlike the relations between the Islamic powers and Christian Europe, Axum, which provided shelter to Muhammad's early followers, was on good terms with its Islamic neighbors.^[7] Nevertheless, as early as 640, Umar ibn al-Khattāb sent a naval expedition against Adulis under Alkama bin Mujazziz, but it was eventually defeated.^[9] Axumite naval power also declined throughout the period, though in 702 Aksumite pirates were able to invade the Hejaz and occupy Jeddah. In retaliation, however, Sulayman ibn Abd al-Malik was able to take the Dahlak Archipelago from Axum, which became Muslim from that point on, though later recovered in the 9th century and vassal to the Emperor of Ethiopia