Muskerry East (Irish: Múscraí Thoir [l 1]) is one of the baronies of Ireland, an historical geographical unit of land.
While the Múscraige petty kingdoms were scattered throughout the province of Munster, the largest were centred on the present baronies of Muskerry (West and East).
[3][4] The main septs were: Rivalry between the princely houses of the outer circle of the Eóganacht would eventually undo the kingdom of Múscraighe Mittaine.
The local Ó Donnagáin dynasty persisted in their opposition to the usurpers, at least until 1115 when they killed the reigning O'Flynn king of Muskerry.
Instead, Henry granted of Dermod's entire kingdom to two of his leading adventurer knights - Robert Fitz-Stephen and Milo de Cogan - in 1177.
According to Giraldus, the grantees took possession of seven cantreds only; three to the east of Cork city were allocated to Fitz-Stephen and four to the west to de Cogan.
An invasion into Múscraighe Mittaine in 1201 in reported in the Annals of Inisfallen as follows:[1] AI1201.12: A mighty hosting this year in Desmumu by William and other foreigners, together with the royalty of all Mumu, i.e. including Muirchertach Ua Briain, Conchobar Ruad, and Donnchad Cairprech, and many others, and their plundering parties were sent against Múscraige Mittaine, and they committed great depredations.
They proceeded thence to Cenn Eich, spent a week there, and made great raids and burned corn crops in every place they came to.
[10] The Cogans conquered most of this area, building castles at Mourne Abbey, Maglin (near Ballincollig), Dundrinan, (Castlemore near Cookstown), Dooniskey, Mahallagh, and Macroom.
In 1398 the Mac Carthys were not alone free to plunder from Dingle to the territory of the Barretts, but could carry on their ancient feud against the Carbery MacCarthys at Carrigrohane.