Énna Aignech ("spirited, swift", an epithet usually applied to horses), son of
Óengus Tuirmech Temrach, was, according to medieval Irish legend and historical tradition, a
High King of Ireland. He took power after killing his predecessor, and relative's killer,
Nia Segamain, and ruled for twenty or twenty-eight years, after which he was killed by
Crimthann Coscrach, the grandson of the man who had killed Énna's grandfather, in the Battle of Ard Crimthainn. Crimthann was killed by Rudraige mac Sithrigi, Énna's great-great-great-great-great-great-great-great-great grandfather killer's great-grandson. The
Lebor Gabála Érenn synchronises his reign with that of
Ptolemy VIII Physcon in
Egypt (145–116 BC). The chronology of
Geoffrey Keating's
Foras Feasa ar Éirinn dates his reign to 219–191 BC, that of the
Annals of the Four Masters to 313–293 BC.