| 104341 | September 12 | Birth | 1988 – Amanda Jenssen, Swedish singer-songwriter and guitarist |
| 104342 | September 12 | Birth | 1989 – Freddie Freeman, American-Canadian baseball player |
| 104343 | September 12 | Birth | 1989 – Andrew Luck, American football player |
| 104344 | September 12 | Birth | 1991 – Scott Wootton, English footballer |
| 104345 | September 12 | Birth | 1992 – Kelsea Ballerini, American singer-songwriter and guitarist |
| 104346 | September 12 | Birth | 1992 – Connor Franta, American blogger and author |
| 104347 | September 12 | Birth | 1992 – Sviatlana Pirazhenka, Belarusian tennis player |
| 104348 | September 12 | Birth | 1994 – Elina Svitolina, Ukrainian tennis player |
| 104349 | September 12 | Birth | 1995 – Ryan Potter, American actor and martial artist |
| 104350 | September 12 | Birth | 1996 – Colin Ford, American actor |
| 104351 | September 12 | Death | 640 – Sak K'uk', Mayan queen |
| 104352 | September 12 | Death | 1185 – Andronikos I Komnenos, Byzantine emperor (b. 1118) |
| 104353 | September 12 | Death | 1213 – Peter II of Aragon (b. 1174) |
| 104354 | September 12 | Death | 1362 – Pope Innocent VI (b. 1295) |
| 104355 | September 12 | Death | 1369 – Blanche of Lancaster (b. 1345) |
| 104356 | September 12 | Death | 1500 – Albert III, Duke of Saxony (b. 1443) |
| 104357 | September 12 | Death | 1612 – Vasili IV of Russia (b. 1552) |
| 104358 | September 12 | Death | 1642 – Henri Coiffier de Ruzé, Marquis of Cinq-Mars, French conspirator (b. 1620) |
| 104359 | September 12 | Death | 1660 – Jacob Cats, Dutch poet, jurist, and politician (b. 1577) |
| 104360 | September 12 | Death | 1665 – Jean Bolland, Belgian priest and hagiographer (b. 1596) |
| 104361 | September 12 | Death | 1672 – Tanneguy Le Fèvre, French scholar and author (b. 1615) |
| 104362 | September 12 | Death | 1683 – Afonso VI of Portugal (b. 1643) |
| 104363 | September 12 | Death | 1691 – John George III, Elector of Saxony (b. 1647) |
| 104364 | September 12 | Death | 1695 – Jacob Abendana, Spanish-English rabbi and scholar (b. 1630) |
| 104365 | September 12 | Death | 1712 – Jan van der Heyden, Dutch painter and illustrator (b. 1637) |
| 104366 | September 12 | Death | 1764 – Jean-Philippe Rameau, French composer and theorist (b. 1683) |
| 104367 | September 12 | Death | 1779 – Richard Grenville-Temple, 2nd Earl Temple, English politician, Lord Lieutenant of Buckinghamshire (b. 1711) |
| 104368 | September 12 | Death | 1810 – Sir Francis Baring, 1st Baronet, English banker and politician (b. 1740) |
| 104369 | September 12 | Death | 1814 – Robert Ross, Irish general (b. 1766) |
| 104370 | September 12 | Death | 1819 – Gebhard Leberecht von Blücher, Prussian general (b. 1742) |