Until the Ethiopian Revolution of 1974, the heads of state of Ethiopia were either emperors or regents.
From the coup d'état of the Derg leading to the fall of the empire in September 1974 until March 1975, the Derg considered the crown prince Asfaw Wossen (later regnal name Amha Selassie) as the king (not emperor) and the nominal head of state – which the crown prince refused to accept.
On 21 March 1975, the Derg military junta abolished the monarchy and fully took over.
The current president is Taye Atske Selassie, elected on 7 October 2024 by members of the Federal Parliamentary Assembly.
Consequently, the numbering starts with the first establishment of the office of the president of Ethiopia in 1987.