The title of "King of Kings", often rendered imprecisely in English as "Emperor", dates back to ancient Mesopotamia, but was used in Axum by King Sembrouthes (c. 250 AD). However, Yuri Kobishchanov dates this usage to the period following the Persian victory over the Romans in 296-297.[3] Its use, from at least the reign of Yekuno Amlak onward, meant that both subordinate officials and tributary rulers, notably the gubernatorial vassals of Gojjam (who ranked 12th in the states non-dynastic protocol as per 1690), Welega, the seaward provinces and later Shewa, received the honorific title of nəgus, a word for "king."
The consort of the Emperor was referred to as the ətege. Empress Zauditu used the feminized form nəgəstä nägäst ("Queen of Kings") to show that she reigned in her own right, and did not use the title of ətege.