I think Constantine. You'll have to check tho!
Constantine the Great was proclaimed emperor in York, England in 306 A.D. after his father's death by the soldiers. Constantine was the first Christian Roman emperor who reigned from 306 to 337 A.D.
Emperor Constantine proclaimed tolerance of Christianity.
he age of a Roman emperor depended on how old he was when he was proclaimed emperor
The Pope placed a crown on his head and proclaimed him "Emperor of the Romans".
Magnentius was proclaimed emperor upon the death of Constans, but his brother, Constantius II was also emperor in the East
me and it was yesterday
Napoleon recognized the independence of HAITI in 1804.
Louis-Napoléon Bonaparte, Napoléon III
Converted his kingdom to Christianity.
Nerva was proclaimed emperor by the senate on the day of the assassination of the emperor Domitian by court officials. He was 65 and childless and had spent much of his career out of public light.
Diocletian was proclaimed emperor in 284 and abdicated in 305. Therefore, his reign lasted 21 years.
Claudius ruled after Caligula. Caligula was murdered by the imperial guard (the Praetorian Guard) who then proclaimed Claudius as emperor.