Brennan Family Crest, Coat of Arms & Brennan Name Origin

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Origin of the Name Brennan

The ancient history of the name Brennan was found in the allfamilycrests.com archives. Variants of the name Brennan include Brannon, Brannan and Brennand. These names are derived from the Gaelic O'Braonain septs whose Gaelic name taken from the Gaelic word 'braon' which has a number of meanings including 'sorrow'. The principal sept of O'Brennan was of Ossory where they were Chiefs of Ui Duach in Northern Kilkenny. In the face of the twelfth century invasion the sept's power waned and by the seventeenth century many of sept were reduced to the status of Rapparee. Another quite different sept was in the Eastern part of County Roscommon, whose Chief was MacBranain. Most of the Chiefs who appear in the Annals between 1159 and 1488 retained the 'Mac' until the submergence of the Gaelic order, when the 'O' prefix began to appear. The County Fermanagh sept of O'Branain also anglicized their name as Brennan as well as Brannan. A fourth sept was located in County Kerry from where their descendants spread to County Cork.