The name Kavanagh or Cavanaugh and the
other variants of the name are derived from the Irish Gaelic name CAOMHÁNACH,
which means 'a student of St. Caomhan' and was first used by Domhnall,
eldest son of the 12th century King of Leinster Diarmait MacMurchad.
Domhnall was fostered for his training
and education at the monastery of St. Caomhan at which is now known as
Kilcavan in the Barony of Gorey, County Wexford. He became known as
Caomhánach, distinguishing him from the other sons of Diarmait. His
brother Eanna became known as Eanna Ceinnsealach, the name of the Clan
land holdings and became the progenitor of the Kinsella Clan.
The Norman knight "Strongbow",
Earl of Stirgoil, leader of the Cambro/Norman invasion of Ireland
married Domhnall's sister Aoife and attempted to commandeer the Kingship
of Leinster following the death of King Dermot MacMurrough in 1171 A.D.
However under Irish (Brehon) law, Strongbow had absolutely no basis for
his claim and was promptly rejected by the Irish chiefs who elected
Domhnall Caomhánach as King.
Strongbow viciously executed Domhnall's
son whom he held as hostage and then bribed two Irish warriors in his
own army to kill Domhnall during the Battle of Naas in 1175 A.D. These
treacherous acts characterized the relationship between the Normans and
the Irish for the following centuries.