On This Day

Newly built city of Constantinople (Byzantium) dedicated to Emperor Constantine the Great, becomes the capital of the Ea

Newly built city of Constantinople (Byzantium) dedicated to Emperor Constantine the Great, becomes the capital of the Eastern Roman Empire

Newly built city of Constantinople (Byzantium) dedicated to Emperor Constantine the Great, becomes the capital of the Eastern Roman Empire

Key People

Constantine the Great

Roman emperor from 306 to 337

Roman emperor from 306 to 337

Events Before

  1. BC Battle of Crannon between Athens and Macedon following the death of Alexander the Great

    The Battle of the Echinades was one of the naval battles of the Lamian War (323–322 BC), fought between the Macedonian navy under Cleitus the White and the Athenian navy.

  2. Battle of Adrianople: Roman Emperor Constantine I defeats his co-emperor Licinius, who flees to Byzantium

    Valerius Licinianus Licinius was Roman emperor from 308 to 324. For most of his reign, he was the colleague and rival of Constantine I, with whom he co-authored the Edict of Milan that granted...

  3. Licinius abdicates his position as Roman Emperor.

    Martinian (Latin: Martinianus; died 325) was Roman emperor from July to September 324.

  4. Old St. Peter's Basilica consecrated in Rome (stood 4th - 16th century), later replaced by current Basilica

    Old St. Peter's Basilica consecrated in Rome (stood 4th - 16th century), later replaced by current Basilica

  5. Athanasius is elected Patriarch bishop of Alexandria

    Athanasius I of Alexandria (296–298 – 2 May 373), also called Athanasius the Great, Athanasius the Confessor, or, among Coptic Christians, Athanasius the Apostolic, was a Christian theologian and the...

Events After

  1. BC Alexander the Great defeats Darius III of Persia in the Battle of Gaugamela

    BC Alexander the Great defeats Darius III of Persia in the Battle of Gaugamela

  2. BC Macedonian army of Alexander the Great defeats Darius III of Persia in the Battle of the Granicus

    The Battle of the Granicus in May 334 BC was the first of three major battles fought between Alexander the Great of Macedon and the Persian Achaemenid Empire.

  3. Church of the Holy Sepulchre is consecrated in Jerusalem

    The Church of the Holy Sepulchre, also known as the Church of the Resurrection, is a fourth-century church in the Christian Quarter of the Old City of Jerusalem.

  4. St Mark is elected Pope

    Pope Mark (Latin: Marcus) was the bishop of Rome from 18 January to his death on 7 October 336. Little is known of Mark's early life.

  5. Pope Saint Mark's death ends his reign as Catholic Pope, leaving the papacy vacant

    Pope Saint Mark's death ends his reign as Catholic Pope, leaving the papacy vacant

More from the 330s

Frequently Asked Questions

What happened on May 11, 330?
Newly built city of Constantinople (Byzantium) dedicated to Emperor Constantine the Great, becomes the capital of the Eastern Roman Empire
Who was involved in Newly built city of Constantinople (Byzantium) dedicated to Emperor Constanti...?
Key figures include Constantine the Great (Roman emperor from 306 to 337).

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