| Era | People | Notes |
| Up to 4000 BCE | Mesolithic | Hunter-gatherers |
| 4000-1800 BCE | Neolithic | Construction of Maes |
| First Farmers | Howe, Callanish, and other megalithic monuments | |
| 1800-1600 BCE | Bronze Age | |
| 1000-Christian Era | Iron Age | |
| 900-500 BCE | Hallstatt | Rise of the Celts |
| 500-15 BCE | La Tene | Heroic Age Celts Most mythologies take place in this period |
| 55-54 BCE | Caesar invades Britain | |
| AD 43-409 | Romano-British | Rome dominates Britain south of Hadrian's Wall (constructed AD 120) |
| AD 409-600 | "Dark Age" Britain | Final Roman withdrawal Patrick's mission to Eire Circa AD 450 Anglo-Saxon invasion |
| Circa AD 500 | Arthur defeats Saxons at Mount Baden | |
| Circa AD 500 | Formation of Dalriada | |
| AD 563 | Saint Columba arrives at Isle of Iona. |
| Letter B L N F S H D T C Q M G Ng St R A O U E I | Name Beth (BETH) Luis (LWEESH) Nionn (NEE-uhn) Fearn (FAIR-n) Saille (SHAL-yuh) Huath (HOO-ah) Duir (DOO-r) Tinne (CHIN-yuh) Coll (CULL) Quert (KWAIRT) Muin (MUHN) Gort (GORT) Ngetal (NYEH-tl) Straiff (STRAHF) Ruis (RWEESH) Ailm (AHL-m) Onn (UHN) Ura (OO-rah) Eadha (EH-yuh) Idho (EE-yoh) | Tree Birch Rowan Ash Alder Willow Hawthorn Oak holly Hazel Apple vine Ivy Reed Blackthorn Elder Silver Fir Furze, or Gorse Heather Poplar Yew |