sky, causing unseasonable weather, crop failures, and famines worldwide. 536: Belisarius captures Rome during the Gothic War (535–554). Beginning of the Byzantine Papacy. 537: The Hagia Sophia, the largest Christian building ever created, is built in Constantinople, becoming a center of Byzantine society for the next millennium. 539/540: Another eruption in the tropics causes another volcanic winter and the Late Antique Little Ice Age. 541-562: Long Lazic War between Eastern Rome and Persia. 542: Plague of Justinian arrives in Constantinople and spreads throughout the Mediterranean Basin and Europe in the 540s, beginning the First plague pandemic which lasted until the 8th century. 546: Ostrogoths under Totila sack Rome. 547: Final volcanic winter of the Late Antique Little Ice Age. 550: Justinianic Church of the Holy Apostles is consecrated in Constantinople. 553: Second Council of Constantinople is convoked by Emperor Justinian I and presided over by Patriarch Eutychius of Constantinople. c. 560: Battle of Gol-Zarriun: The Hephthalite Empire is dissolved into minor kingdoms by a combined attack of Persia and the Western Turkic Khaganate. 567: Lombard–Gepid War (567): The Gepid kingdom in Pannonia is destroyed by the Lombards and Avars. The Lombards will invade Italy the following year. 572-591: Byzantine–Sasanian War of 572–591: Long conflict in the Caucasus. 575/578: Sasanian reconquest of Yemen. 582-602: Maurice's Balkan campaigns are the last defense of the Danube frontier. 585: The Kingdom of the Suebi in Gallaecia is destroyed by the Visigothic King Liuvigild. 602: The beginning of the final Byzantine-Sassanian War, lasting until 628. War encompasses entire Near East, exhausting both combatants. 609: The emperor Phocas gives the Pantheon, Rome to Pope Boniface IV and it becomes a church. 622: The Hijrah: Muhammad and Abu Bakr flee Mecca for Medina and begin the Islamic community. 626: Avar, Slav, and Sasanian Siege of Constantinople. 626: Slav tribes in Moravia and Pannonia, led by the Frankish merchant Samo rebel against the Avar khagan, establishing the Samo's Empire, the first Slavic state. 630: In the Pontic steppes, the Khazar Khaganate is formed, after the disintegration of the Western Turkic Khaganate. 634: The Battle of al-Qaryatayn: beginning of the Arab conquest of Syria. 636: Battle of al-Qadisiyyah: Conquest of Mesopotamia by the Rashidun Caliphate. 636: Battle of the Yarmuk: Conquest of Levant by the Arab general Khalid ibn al-Walid. 640: Battle of Heliopolis: Arab general Amr ibn al-A'as begins the Muslim conquest of Egypt. 641: Battle of Nahavand: