618

By place

Byzantine Empire

• Byzantine–Sassanian War: A Persian expeditionary force under Shahrbaraz invades Egypt, and occupies the province. After defeating the Byzantine garrisons in the Nile Valley, the Persians march across the Libyan Desert as far as Cyrene.
• The Persians besiege Alexandria; the defence of the city is led by Nicetas. The Byzantine resistance is undermined by a blockade of the harbor; the usual grain supplies are cut off from Egypt to Constantinople.

  Asia

• June 18 - The Sui dynasty ends: The rebel leader Li Yuan captures Luoyang, and has Emperor Yángdi murdered. He proclaims himself emperor Gao Zu and establishes the Tang dynasty, one of the most notable dynasties in Chinese history, which will last for almost 300 years.
• October 6 - Wang Shichong decisively defeats Li Mi at the Battle of Yanshi, during the transition from Sui to Tang civil war.
• November 29 - Battle of Qianshuiyuan: The Tang dynasty scores a decisive victory over their rival Xue Rengao.
• Tong Yabghu Qaghan becomes the new ruler of the Western Turkic Khaganate, founding the Khazar Khaganate. He maintains close relations with the Tang dynasty, and possibly marries into the imperial family.
• Songtsän Gampo becomes the first emperor of the Tibetan Empire, after his father Namri Songtsen is poisoned. During his reign he expands Tibet's power beyond Lhasa and the Yarlung Valley.
• Yeongnyu becomes ruler of the Korean kingdom of Goguryeo.