When was the Kingdom of Aksum founded?
Kingdom of Aksum
1st century AD
The Kingdom of Aksum (also known as the Kingdom of Axum, or the Aksumite Empire) was an ancient kingdom located in what is now Tigray Region (northern Ethiopia) and Eritrea.[2][3]. Axumite Emperors were powerful sovereigns, styling themselves King of kings, king of Aksum, Himyar, Raydan, Saba, Salhen, Tsiyamo, Beja and of Kush.[4]
Ruled by the Aksumites, it existed from approximately 100 AD to 940 AD. The polity was centered in the city of Axum and grew from the proto-Aksumite Iron Age period around the 4th century BC to achieve prominence by the 1st century AD. 
Aksum became a major player on the commercial route between the Roman Empire and Ancient India. The Aksumite rulers facilitated trade by minting their own Aksumite currency, with the state establishing its hegemony over the declining Kingdom of Kush. It also regularly entered the politics of the kingdoms on the Arabian Peninsula and eventually extended its rule over the region with the conquest of the Himyarite Kingdom. The Manichaei prophet Mani (died 274 AD) regarded Axum as one of the four great powers of his time, the others being Persia, Rome, and China.[2][5]