540s

Below are some of the important events that happened from 540 to 549. It is distinct from the decade known as the 50th decade which began on January 1, 541 and ended on December 31, 550.

• Emperor Kimmei, reign of 29th emperor of Japan starts (540-571)^[1]
• Vitiges of the Ostrogoths surrendered to the Byzantine army.^[2]

• Authari, king of the Lombards
• Pope Gregory I (approximate date)^[3]
• Myrddin Wyllt, Welsh legend (approximate date)

• Dignāga, Buddhist founder of Indian logic
• Dionysius Exiguus (approximate date)
• Empress Yujiulü, empress of Western Wei
• Empress Yifu, empress of Western Wei
• Fridolin of Säckingen Irish missionary
• Vedast, Frankish bishop
• Vitiges, king of the Ostrogoths

• Plague of Justinian: Bubonic plague appears suddenly in the Egyptian port of Pelusium. It spreads to Alexandria and, the following year, to Constantinople. This is the beginning of a 200-year long pandemic that will devastate Europe, the Middle East, and North Africa.
• Totila is elected king by the Ostrogothic nobles after the death of his uncle Ildibad.
• The Uyghurs come under the rule of the Hephthalites

• July 21 – Wéndi, emperor of the Sui Dynasty

• Adhurgunbadh, Persian general
• Eraric, king of the Ostrogoths
• Ildibad, king of the Ostrogoths

• Plague of Justinian: Bubonic plague kills at least 230,000 in Constantinople.
• King Childebert I and his brother Chlothar I invade Visigothic Spain.

• Xiao Min Di, emperor of Northern Zhou
• Xiao Ming Di, emperor of the Liang Dynasty

• August 27 – Caesarius, bishop of Arles

• The Byzantine garrison (1,000 men) in Naples surrenders to the Ostrogoths.
• King Khosrau I invades Syria.
• The Hephthalites threaten the Persian Empire from the East. They extend their gain more territory in Central Asia.
• King Pulakesi I starts the Chalukya Dynasty.

• Brunhilda, queen of Austrasia (approximate date)
• Jing Di, emperor of the Liang Dynasty
• Wu Di, emperor of Northern Zhou

• Octa, king of Kent (approximate date)

• Belisarius defeats the Gothic army under king Totila.
• King Khosrau I unsuccessfully attacks the Byzantine city of Dara.
• Ly Bi is made emperor and starts the empire Van Xuân (modern Vietnam).

• Dugu Qieluo, empress of the Sui Dynasty
• Jing Di, emperor of the Liang Dynasty
• Yuwen Xian, prince of Northern Zhou

• Solomon, Byzantine general
• October 18 – Saint Wenna

• King Khosrau I signs a five-year truce with the Byzantine Empire.

• Abd Allah ibn Abd al Muttalib, father of Muhammad
• Fei Di, emperor of Northern Qi

• Budic II, king of Brittany (approximate date)
• Clotilde, Burgundian princess
• Medardus, bishop of Vermandois (approximate date)
• Stotzas, Byzantine rebel leader

• The Ostrogoths under king Totila retake Rome.
• Audoin succeeds Walthari as king of the Lombards.
• Audoin leads the Lombards across the Danube and becomes an ally of the Byzantines.

• Walthari, king of the Lombards

• Belisarius recaptures Rome from the Ostrogoths.
• Theodebald becomes king of Austrasia.
• King Ida starts the kingdom of Bernicia. He builds Bamburgh Castle.
• The Tonkin revolt is stopped by the Chinese Liang Dynasty.

• Pei Ju
• Empress Zhu Manyue

• Theodebert I, king of Austrasia (or 548)
• Tribonian, Byzantine lawyer and writer of the Codex Justinianus.
• Maelgwn Gwynedd, king of Gwynedd (approximate date)
• Gao Huan

• Emperor Justinian I removes Belisarius from military service.
• Theudigisel names himself ruler over the Visigothic Kingdom.

• Xiao Zhuang, crown prince of the Southern Dynasties (approximate date)

• April 13 – Ly Nam De, emperor of Vietnam
• Theodebert I, king of Austrasia (or 547)
• June 28 – Theodora I, Byzantine Empress
• Theudis, king of the Visigoths

• Jianwen Di becomes ruler of the Liang Dynasty in China.
• Agila becomes king of the Visigoths.
• The Roman Catholic Diocese of Ossory is founded in Ireland.
• The Ostrogoths under Totila recapture Rome.
• Totila conquers the city of Perugia.

• Jizang, Chinese Buddhist monk

• Theudigisel, king of the Visigoths
• Tuathal Maelgarb, King of Tara
• Gao Cheng
• Emperor Wu of Liang
• Xiao Zhengde
• Princess Xu Zhaopei
• Zhu Yi