Fergus mac Léti

"Fergus goes down into the lake", illustration by Stephen Reid in T. W. Rolleston's The High Deeds of Finn (1910)

Fergus mac Léti (also mac Léte, mac Léide, mac Leda) was, according to Irish legend and traditional history, a king of Ulster. His place in the traditional chronology is not certain – according to some sources, he was a contemporary of the High King Conn of the Hundred Battles, in others of Lugaid Luaigne, Congal Cláiringnech, Dui Dallta Dedad and Fachtna Fáthach.