LYOR nah HWID-reh
Ireland's oldest surviving manuscript written entirely in Irish, compiled around 1106.
Compiled at the monastery of Clonmacnoise, Lebor na hUidre is the earliest surviving manuscript containing a version of the Táin Bó Cúailnge, along with other Ulster Cycle material, making it one of the foundational physical sources for the whole tradition.
Lebor na hUidre means "Book of the Dun Cow". It is thought to have been written around 1100 at Clonmacnoise, and later tradition said it was made from the hide of a cow belonging to Saint Ciarán, the monastery's founder. The manuscript survives only in part and is kept by the Royal Irish Academy in Dublin.
Its importance is that it is one of the oldest books in Irish to contain native secular stories. Alongside the Táin, it preserves tales from the Ulster and Mythological Cycles, and its pages show the work of several scribes and later correctors, so it is also a record of how the stories were copied and revised.
| Cycle | Entries here | Focus |
|---|---|---|
| The Mythological Cycle | 21 | The oldest of the four cycles, telling of the Tuatha Dé Danann and the successive invasions of Ireland. |
| The Fenian Cycle | 7 | Tales of Fionn mac Cumhaill and his band of warriors, the Fianna, set generations after the Ulster Cycle in a world of hunting, romance, and roaming adventure. |
| The Ulster Cycle | 12 | The heroic tales of Conchobar mac Nessa's court at Emain Macha, centered on Cú Chulainn and the great cattle raid of the Táin Bó Cúailnge. |
| The Historical Cycle | 1 | Also the Cycle of the Kings — legendary and semi-legendary tales of Ireland's High Kings, treated by medieval scribes as genuine national history. |
Lebor na hUidre ("The Book of the Dun Cow") is the oldest surviving manuscript written substantially in Irish, compiled around 1106 AD at the monastery of Clonmacnoise, and a key source for the Ulster Cycle including an early version of the Táin Bó Cúailnge.
Tradition holds its vellum pages were made from the hide of a cow belonging to St. Ciarán, the founder of Clonmacnoise, giving the manuscript its distinctive name.
It survives only in fragmentary form — about 67 leaves — having been damaged and had material removed over its long history, yet it remains one of the most important surviving witnesses to early Irish literature.