Eolais was born into a
Túath of
the Conmaicne settled in present-day
south county Leitrim, in the second half of the 9th century. As an adult, he became chieftain of his sept. A charismatic leader, he became the first full chieftain of the "
Conmaicne Réin" AD 900. He married, having at least three sons, named "
Brocan", the ancestor of Shanley; "
Anbeith", the ancestor of Mac Garry; and "
Maolmuire", lord of
Conmaicne Réin and ancestor of Mag Raghnaill (anglicised Mac Rannell, Reynolds).
Ódhrán Ua hEolais, a famous scribe of
Clonmacnoise, was probably his grandson. Eolais's death is not recorded by the
Irish Annals, but probably occurred between A.D. 920–960. ==Legacy==