According to Ethiopian tradition the word “Ethiopia” is derived from the word “Ethiopis”, the name of an Ethiopian King. The Ethiopian book of Aksum identifies him as the 12th king of Ethiopia.
1871BCE-1856BCE: Reign of Kushite King Etiyopus I of Kerma
Prior to Greek history, Ethiopia was known as "Kush" by the ancient "Egyptians." The Buhen stela which dates from the reign of Sety I (1294-1279 BC), refers to this region as "KAS" and "KASH" Kush is also mentioned as "KSH" in other texts dated between 1550 - 1069 BC.
In his works titled "THE GENETIC UNITY OF BLACK AFRICAN", Clyde Winters suggests that:
"In the ancient inscriptions of Africa and Asia the Kushites were called many names including Kush, and Ethiopian by the Greeks and Romans. In Sumerian inscriptions the Kushites were called Meluha=Kasi < Kush . There is historical evidence that suggest that the name Meluha, was a geographical name for the Africans who lived in the area of Nubia and Northwest Africa. The people of Nubia are mostly associated with the name Kushite were the C-Group culture group, worshipers of Amon and Neith. The Egyptian term for these people was K-'-sh and K-'-sh-i. The Hebrews called them Kush. In the cuneiform inscriptions the Sudanese were called Kushiya."
THE GENETIC UNITY OF BLACK AFRICAN
Ezana is responsible for the conquest of Nubia (Meroitic Kush). But Nubia does not convert to Christianity upon Ezana's conquest. Before the Ethiopian king Ezana (whose kingdom was then called Aksum) embraced Christianity for himself and decreed it for his kingdom (c. 330 A.D.), his nation had already constituted a large number of Christians.
Rather Nubia's conversion begins in 542AD when two missionary groups set out to gain converts to their cause. One group was the Monophysites, under the patronage of Emperor Justinian, and the other was the Melkites, under the patronage of the Empress Theodora. Through some crafty political maneuvering, the Monphysites manage to reach the Nubian kingdoms and by 580AD they had accepted Coptic (Egyptian) Christianity. Christianity flourished in the Nubian kingdoms mostly among the royalty and the monks; it is unknown whether the general populace fully embraced the religion
The Aksumite Negusa-Nagast, Ezana I (330-356)