|543 by topic|
|Ab urbe condita||1296|
|Balinese saka calendar||464–465|
|Chinese calendar||壬戌年 (Water Dog)|
3239 or 3179
— to —
癸亥年 (Water Pig)
3240 or 3180
|- Vikram Samvat||599–600|
|- Shaka Samvat||464–465|
|- Kali Yuga||3643–3644|
|Iranian calendar||79 BP – 78 BP|
|Islamic calendar||81 BH – 80 BH|
|Minguo calendar||1369 before ROC|
|Seleucid era||854/855 AG|
|Thai solar calendar||1085–1086|
669 or 288 or −484
— to —
670 or 289 or −483
Year 543 (DXLIII) was a common year starting on Thursday of the Julian calendar, the 543rd year of the Common Era (CE) and Anno Domini (AD) designations, the 543rd year of the 1st millennium, the 43rd year of the 6th century, and the 4th year of the 540s decade. As of the start of 543, the Gregorian calendar was 2 days ahead of the Julian calendar, which was the dominant calendar of the time.
- Spring – Siege of Naples (542–543): The Byzantine garrison (1,000 men) in Naples surrenders to the Ostrogoths, pressed by famine and demoralized by the failure of two relief efforts. The defenders are well treated by King Totila, and the garrison is allowed safe departure, but the city walls are partly razed.
- The fortress city of Old Dongola (modern Sudan) along the River Nile becomes the capital of the Kingdom of Makuria. Several churches are built, including the "Old Church" (approximate date).
- Summer – Khosrow I, Shahanshah of the Sasanian Empire, invades Syria again, and turns south towards Edessa to besiege the fortress city.
- The Hephthalites threaten the Sasanian Empire from the East. They extend their domain in Central Asia (approximate date).
- A Byzantine invasion of Persarmenia is defeated at the Battle of Anglon by a much smaller force from the Sasanian Empire.
- King Pulakeshin I establishes the Chalukya dynasty in India. He extends his kingdom by conquering Vakataka and the west coast of Karnataka, giving him access to the valuable Arabian Sea trade routes.
- Approximate date – The Yupian (玉篇) Chinese dictionary is edited by Gu Yewang.
- The doctrine of apocatastasis is condemned by the Synod of Constantinople.
- Brunhilda, queen of Austrasia (approximate date)
- Columbanus, Irish missionary (d. 615)
- Jing Di, emperor of the Liang Dynasty (d. 558)
- Wu Di, emperor of Northern Zhou (d. 578)
- Octa, king of Kent (approximate date) (b. 500)
- Adolius, Byzantine officer
- ^ Bury (1923). Vol. II, Chapter XIX, p. 231-233.
- ^ Bauer, Susan Wise (2010). The History of the Medieval World: "From the Conversion of Constantine to the First Crusade". ISBN 978-0-393-05975-5 p. 231.