Ériu

Ériu is one of three sister goddesses of the Tuatha Dé Danann — alongside Banba and Fódla — each associated with the sovereignty of Ireland itself. When the Milesians (the Sons of Míl) land to take the island by force, each of the three sisters meets the invaders in turn and asks that the land be named for her. The poet Amergin, speaking on behalf of the Milesians, grants each request, but it is Ériu's name that endures: the modern Irish name for the country, Éire, and the English "Ireland," both descend from hers. As a sovereignty goddess, Ériu embodies the land as something a king must be joined to rather than simply rule over — a recurring idea across Irish myth in which kingship is legitimized through union with the goddess of the territory, rather than by conquest alone. Her sisters Banba and Fódla still appear as poetic names for Ireland in later literature, but it is Ériu's alone that became the country's actual name in two languages. The genealogies preserved in the Lebor Gabála Érenn ("The Book of Invasions") place Ériu among the Tuatha Dé Danann's ruling generation, married to Mac Gréine, one of three joint kings of Ireland at the time of the Milesian invasion (his brothers Mac Cuill and Mac Cecht are married in turn to her sisters). After the Milesians' victory, tradition holds that Ériu and the rest of the Tuatha Dé Danann withdrew into the sídhe — the otherworldly mounds — rather than vanishing from the land altogether.