Brittany, France). Some of these sailors probably migrated to Cornwall, and later to south-eastern Ireland where they became known as the Venii and grew in power. They worshipped a ram god and sometimes called themselves Ghaisonli ('spear-men'), possibly to compete in propaganda with the Lagini ('lance-men'). The southern Venii came to be known as the Eoghanacht, while another group of them migrated north and formed a new kingdom west of the River Shannon where they became known as the Connachta after a revered leader named Conn. These Connachta later extended their power eastward into the plain of Meath, and under the leader Teutovalos Teachtmhar overthrew the kingship of the Lagini at Tara around AD 300. As the Celtic language in Ireland transformed into Irish between AD 400–500, Venii became Féni, and were also known to have called themselves Gaídhil (from Common Celtic *wēdelos, Brythonic gwddel, Goidelic *wēdus to Old Irish Goídel—meaning savage woodsman, wild, raider). The Primitive Irish Vendo is a cognate with Finn, and the Fianna were landless, aristocratic young men and women who had not yet come into their inheritance of land. Niall, the son of Ivocatus Magumedonus ('Eochaidh the Slave-ruler'), came to lead the Connachta in the fifth century AD. Legendary biography A biography of Niall can be constructed from sources such as the "Roll of Kings" section of the 11th-century Lebor Gabála Érenn, the Annals of the Four Masters, compiled in the 17th-century, chronicles such as Geoffrey Keating's Foras Feasa ar Éirinn (1634), and legendary tales like the 11th-century "The Adventure of the Sons of Eochaid Mugmedon" and "The Death of Niall of the Nine Hostages". These sources date from long after Niall's time and they have little to no value as history. Early life A legendary account of Niall's birth and early life is given in the possibly-11th-century tale Echtra mac nEchach Muimedóin ("The adventure of the sons of Eochaid Mugmedón"). In it, Eochaid Mugmedón, the High King of Ireland, had five sons: Four, Brión, Ailill, Fiachrae and Fergus, by his first wife Mongfind, sister of the king of Munster, Crimthann mac Fidaig; and a fifth, Niall, by his second wife Cairenn Chasdub, daughter of Sachell Balb, king of the Saxons. While Cairenn is pregnant with Niall, the jealous Mongfind forces her to do heavy work, hoping to make her miscarry. She gives birth as she is drawing water, but out of fear of Mongfind,