Keegan

MacEgan Mac Aodhagáin
Country	Kingdom of Connacht
Parent house	Uí Maine
Titles	Hereditary Brehons of Ireland Ollam to the Ó Conchobhair Ollam to the Mac William Uachtar Ollam to the Mac William Iochtar Ollam to the Conmhaícne Ollam to the Uí Briúin Bréifne Ollam to the Tethbae Ollam to the Ó Fearghail Ollam to the Ó Conchobhair Uí Failghe
Founder	Aedhaghan mac Gosda

Mac Aodhagáin (English: Egan or Keegan), is an Irish Gaelic clan of Brehons who were hereditary lawyers - firstly to the Ó Conchobhair Kings of Connacht, and later to the Burkes of Clanricarde.

The earliest surviving Irish law manuscript, In Senchas Már, was written prior to 1350 at a school (patronised by the Mac Aodhagáin) at Duniry, near Loughrea. Other branches of the clann maintained schools at Park, outside Tuam, and at Ballymacegan in Co. Tipperary. The work known as Leabhar Breac was produced by one of their students, while Dubhaltach MacFhirbhisigh may have studied at Ballymacegan under Flann Mac Aodhagáin up to the year 1643.

The surname has been Anglicised in a variety of ways, including as Mac Egan, Egan, Eagan, Keegan, or Keigan, McKiegan, and McKagan.

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