After the temporary setback regarding his naval landings in the Fourth Punic War, Imperator Caesar Flavius Valerius Leo Thrax Magnus Pius Felix Invictus Augustus returned to his capital of Constantinople–New Rome, the Queen of Cities, to regroup and re-plan. However, Imperator Leo Thrax Magnus was an old man. So, he died a natural death from old age.

Fortunately, Imperator Leo Thrax Magnus had been prudent enough to get all of his affairs in order before he kicked the can. His heir apparent, Nobilissimus Caesar Flavius Zeno Trascalissaeus Rousombladadiotes, Magister Militum Praesentalis et Comes Excubitorum, was duly acclaimed Imperator Caesar Flavius Zeno Trascalissaeus Rousombladadiotes Pius Felix Invictus Augustus by the Army, the People, and the Senate of the Eastern half of the Roman Empire, and then crowned by the Ecuminical Patriarch himself.

The new Imperator Zeno's himself was getting on his years, but his own son and heir, named Leo in honour of his grandfather, was a mere boy of 10 or so, so he'd be able to rule a long and full reign after Imperator Zeno ascended to Heaven. The younger Leo was quickly appointed Nobilissimus Caesar, to formalize his position as junior emperor of the East, and heir apparent to Imperator Zeno.