How did constantinople became Rome's second capital?

Answer 1

The Western Roman Empire was quickly declining and sinking into the 'dark ages'. In 331AD Emperor Constantine moved the Capital from the city of Rome to the city of Byzantium and renamed it Constantinople. Constantinople geographic location gave it supreme strategi placement and incredible amounts of wealth. It was situated in the center of what remained of the Roman Empire which also made it very appealing.

Answer 2

The Roman Empire had four capitals before Constantinople. The emperor Diocletian had formed the tetrarchy (rule by four) which was a co-emeperorship with two senior emperors and two junior ones. Each emperor had an imperial seat: Nicomedia (present day Izmit, in northwestern Turkey), Sirmium (modern Sremska Mitrovica in Serbia), Mediolanum (modern Milan in Italy) and Augusta Treverorum (modern Trier, in Germany). Rome ceased to be the capital of the Roman Empire.

Constantine the Great ended the tetrarchy by winning to civil wars and became the sole emperor. He decided to create his own capital. He redeveloped Byzantium (modern Istanbul in Turkey) and renamed it after himself - Constantinople means city of Constantine. Later a co-emperoship with one emperora in charge of the eastern pert of the Roman Empire and the other in charge of the western part, Constantinople was the capital of the east and Milan was the capital of the west.

Answer 3

Constantinople became the capital of the Byzantine Empire under Emperor Constantine the Great around 330 AD.