The Byzantine Empire had its first golden age under the Justinian Dynasty, which began in 518 AD with the Accession of Justin I. Under the Justinian Dynasty, particularly the reign of Justinian I, the Empire reached its largest territorial point, reincorporating North Africa, southern Illyria, southern Spain, and Italy into the Empire. The Justinian Dynasty ended in 602 with the deposition of Maurice and the ascension of his successor, Phocas.

The Justinian Dynasty began with the accession of its namesake Justin I to the throne. Justin I was born in a small village, Bederiana, in the 450s AD. Like many country youths, he went to Constantinople and enlisted in the army, where, due to his physical abilities, he became a part of the Excubitors, the palace guards. He fought in the Isaurian and Persian wars, and rose through the ranks to become the commander of the Excubitors, which was a very influential position. In this time, he also achieved the rank of senator. After the death of the Emperor Anastasius, who had left no clear heir, there was much dispute as to who would become emperor. To decide who would ascend the throne, a grand meeting was called in the hippodrome. The Byzantine Senate, meanwhile, gathered in the great hall of the palace. As the senate wanted to avoid outside involvement and influence, they were pressed to quickly select a candidate; however, they could not agree. Several candidates were nominated, but were rejected for various reasons. After much arguing, the senate chose to nominate Justin; and he was crowned by the Patriarch of Constantinople John of Cappadocia on 10 July.

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