| Date | Event |
|---|---|
| 312 | Constantine “converted” to Christianity |
| 314 | Paschal Controversy: Council of Arles |
| 350? | Ninian of Galloway |
| 371 | Birth of Patrick (Annals of 4 Masters) |
| 385? (371?) | Birth of Patrick |
| 395 - 430 | Augustine bishop of Hippo. |
| 387 - 393 | Patrick as slave in Ireland (at age 16 - 22). |
| 395+ | British ask Rome for support against Irish raiders. |
| 400 | Pelagius (British) and Coelestius (Irish) in Rome. |
| 405 (387?) | Patrick as slave in Ireland (at age 16 - 22) |
| 408 | Invasion of Italy by Visigoths. |
| 410 | Romans leave Britain. |
| 411 (393?) | Patrick’s escape |
| 414 (432?) | Patrick’s mission to Ireland (at least 45 years old). |
| 429 | Germanus first arrival in Britain to combat Pelagianism. |
| 431 | Pelladius sent to Ireland by Celestine |
| 432 (414?) | Patrick’s mission to Ireland |
| 432 | Death of Ninian |
| 447 | Germanus second arrival in Britain |
| 440-450 | Anglo-Saxon Invasion |
| 450 (?) | "Birth" of Brigit of Kildare (?) |
| 454 | Paschal Controversy: intro of Victorian Cycle (mainland Europe) to replace what became known as Celtic-84 |
| 455 | Vandals sack Rome |
| 461 460? 465? | Death of Patrick? |
| 476-480 | End of Western Roman Empire |
| 484 | Birth of Brendan |
| 484 | Enda of Aran founds monastery in Inishmore |
| 490? | Victory of Britons (King Arthur?) over the Anglo-Saxons. |
| 500 | Búite establishes Monasterboice |
| 520 | Death of Brigit of Kildare (?) |
| 525 | Paschal Controversy: intro of Dionisiac Cycle. |
| 521 | Birth of Columcille (Gartan, Co. Donegal) |
| 530 | Death of Arthur |
| 530 | Finnian establishes Clonard |
| 530 | Finnian trains “twelve apostles of Ireland” Ciaran of Saiger, Ciaran of Clonmacnois, Brendan of Clonfert, Brendan of Birr, Columcille of Derry, Durrow and Iona, Colmán of Terryglass, Molaisse of Devenish, Canice of Aghaboe, Ruadán of Lorrha, Mobhi of Glasnevin, Sinell of Cleenish, Ninidh of Inishmacsaint. |
| 543 | Birth of Columban (Leinster) |
| 540 | Death of Enda of Aran |
| 542-549 | The Plague, natural disasters, crop failure, famine throughout Europe |
| 549 | Death of Finnian of Clonard (by the Plague) |
| 558 | Brendan ‘the Navigator’ founds Clonfert. |
| 558 | Comgall founds Bangor. |
| 563 | Battle of Cúl Dreimne |
| 565 | Columcille founds Iona |
| 577 (583?) | Death of Brendan of Clonfert |
| 590/1 (585?) | Columban (with 12 companions) leaves Ireland. |
| 597 | Death of Columcille |
| 597 | Augustine sent by Gregory the Great to Britain |
| 605 | Death of Augustine |
| 615 | Death of Columban |
| 626 | Conversion of Northumbria |
| 629 | Mag Lena (Birr) synod relating to Paschal Controversy (delegation to Rome) |
| 634 | Birth of Cuthbert and Wilfrid |
| 635 | Aidan at Lindisfarne |
| 640 | Death of Gall |
| 640-650 | Anon (Armagh?) writes ‘Book of the Angel’ |
| 651 | Death of Aidan |
| 664 | Synod at Whitby, Colmán resigns his see (Lindisfarne), travels to Ireland. |
| 664 | Yellow Plague |
| 661-700 | Muirchú (Armagh) writes ‘Life of Patrick’. |
| 668-720 | Tírechán (Mayo) writes ‘Brief Account’ of Patrick. |
| 688-704 | Adomnan (Iona) writes ‘Life of Columcille’. |
| 695 | Willibrord (658 – 739 Irish) Apostle of the Frisians became bishop of Utrecht. |
| 697 | Synod of Birr, conformance of Ireland south. |
| 716 | Iona conforms to Roman position. |
| 717 | King Nectan banishes the Iona community. (?) |
| 731 | Bede (672-735) finishes his Ecclesiastical History |
| 740 (?) | Aethelwold last Celtic bishop of Lindisfarne |
| 754 | Death of Boniface, apostle of Germany “authorized reformer from Rome” |
| 768 | Wales conforms to Roman position. |
| 775 – 850 (approx) | Invasion of the Danes |
| 1134-1148 | Malachy, bishop of Armagh |
| 1152 | Synod of Kells. |
| 1166 | Invasion of Ireland by Henry II. |
| 1172 | Synod of Cashel, Irish Church loses its independence. |