Events and trends

• 630—Serbs and Croats settle the Balkans in the provinces of Moesia, Pannonia and Dalmatia
• 632—Death of Muhammad and transfer of authority in Islam to first caliph.
• 632—The Muslims under the new caliph Abu Bakr begin the wars of Apostasy or Ridda Wars against the self-proclaimed prophet Musaylimah.
• 633—Around this time Isidore of Seville completes his Etymologies
• 633—The Ridda Wars ends and all Arabia is once again united.
• 633—The Muslim Arabs start to plunder the border cities of the Sassanian Empire.
• 633—The Muslim Arabs defeat the Sassanians in the Battle of Chains.
• 633—The Sassanians are defeated once more by the Muslim Arabs in the Battle of River.
• 633—The Sassanian Empire is again defeated by the Muslim Arabs in the Battle of Walaja.
• 633—The Muslim Arabs conquer the great fortress city of Hira, capital of Mesopotamia from the Sassanian Empire.
• 636—Battle of Yarmouk against the Byzantine Empire led to the conquest of the Levant by generals Amr ibn al-A'as, Khalid ibn al-Walid, Abu Ubaidah ibn al-Jarrah, Yazid ibn Abu Sufyan and Shurahbil ibn Hassana under Caliph Umar ibn al-Khattab.
• 636—Around this time the Battle of al-Qādisiyyah resulted in a decisive victory for Muslims in the Islamic conquest of Persia by General Sa`d ibn Abi Waqqas under Caliph Umar ibn al-Khattab.
• 637—Occupation of Mesopotamia by followers of Prophet Muhammad
• 639—Plague of Emmaus