O Flanagan - Irish / Ua Flannagain - flann / red or ruddy. An important Heremonian Ui Cobhthaigh Dal Cuinn Ui Briuin Ai Sept / Family branch of the Siol Muiredaig / Sil Murray Ui Conchobhair Tuath / Family region who were kinsmen to the O Connor Kings of Connacht and Ireland. Their territory was originally in parts of Co. Fermanagh in the south - west of the Ulster Province and nearby in Co. Roscommon in the east of the Connacht Province where they were Chiefs and Kings. They were also nearby in Co. Offaly in the north - west of Southern Leinster. Ancestors - *103.Conor / Conchobar the 38th King of Connacht (Ui Conchobair), *101.Muirgius the 31st King of Connacht, *98.Indrechtach the 21st King of Connacht, *97.Murray / Muiredach the 18th King of Connacht (Siol Muiredaig), *96.Fergus / Muirgius, *95.Reilly / Ragallach the 12th King of Connacht (Ui Briuin Ai) *87.Brion the original 1st King of Connacht (Ui Briuin), *80.Conn of the Hundred Battles the 110th King of Tara / Ireland (Dal Cuinn).

O Flanagan - Irish / Ua Flannagain. A Heremonian Ui Cobhthaigh Dal Cuinn "Southern" Ui Niaill Cenel Cairbre Sept / Family branch from the Tuath Ratha - Toora, who had their territory in Co. Fermanagh in the south - west of the Ulster Province. Ancestors - *90.Toole / Tuathal "Mael Garb" the 132nd King of Tara / Ireland, *89.Cormac "Caech," *88.Cairbre / Coirpre, *87.Niall of the Nine Hostages the 126th King of Tara / Ireland (Ui Niaill), *80.Conn of the Hundred Battles the 110th King of Tara / Ireland (Dal Cuinn).

O Flanagan - Irish / Ua Flannagain. A Heremonian Ui Cobhthaigh Dal Cuinn Colla da Crioch Siol Daim Argait (Ui Cremthainn) Clan Ceallaigh Sept / Family branch, who had their territory in Co. Monaghan in Southern Ulster. (Descended from *Flanagan O Donnell of the Clan Kelly.) Kinsmen to the Mac Donnells / Mheic Domhnaill the Kings of Clan Kelly who had their territory nearby at Lisnakea in Co. Fermanagh in the south - west of the Ulster Province. Ancestors - *Flanagan O Donnell, *97. Kelly, *92.Daimine, *91.Cairpre "Dam Argait," *90.Eochu / Echach, *89.Criffan / Crimthann "Lethan," *88.Fiacc, *87.Daig "Duirn," *86.Rochadh, *85.Murray / Muiredach Colla "da Crioch" / "Focrith"- of the Two Countries, *84.Eochy / Echu "Doimhlen," *83.Cairbre "Liffeachair" the 116th King of Tara / Ireland.

O Flanagan. A Heberian Cianacht Cenel Aga Sept / Family branch. Ancestors - *89.Feigth, *88.Fionnachta the direct ancestor of the O Meaghers / O Mahers, *87.Connla / Conley the ancestor of the Cianachta (Ui Conchaibhain) Sept in the Ulster Province, *86.Teague / Tadhg mac Cian, *85.Cian (Cianachta), *84.Ailill "Oluimm" the 1st King of Munster.

O Flanahy - Irish / Ua Flannchaidh. A Sept / Family branch, who had their territory in the Heberian kingdom of Thomond / Tuaisceart Mhumhain / Northern Munster.

O Flannelly - Irish / Ua Flannghaile - flann / red - ghaile / valour. A Sept / Family branch who were Kings and had their territory in Co. Sligo in the north - west of the Connacht Province. Often confused with O Flannery.

O Flannery - Irish / Ua Flannabhra - flann / red - abhar / eyebrows. A Heremonian Ui Cobhthaigh Dal Cuinn Ui Fiachrach Sept / Family branch, who had their territory in Co. Mayo in the mid - west of the Connacht Province. Ancestors - *87.Fiachra the original 2nd King of Connacht (Ui Fiachrach), *88.Eochy "Mugmedon" the 124th King of Tara / Ireland, *80.Conn of the Hundred Battles the 110th King of Tara / Ireland (Dal Cuinn).

O Flannery - Irish / Ua Flannabhra - flann / red - abhar / eyebrows. A Heberian Eoghanacht Ui Fidgeinti Sept / Family branch who were the Chiefs of the Dal Cairbre Eva with the O Clerkins in their territory in the Barony of Kenry in Co. Limerick in the mid - north - west of Thomond / Tuaiscert Mhumhain / Northern Munster. Ancestors - *91.Cairbre / Coirpre (Ui Coirpre Aebda,), *90.Brion (Ui Fidgeinti), *89.Fiachu "Fidgennid," *88.Maine "Munchain," *87.Ailill "Fland Bec," *86.Fiachu "Mullethan,"*85.Eoghan "Mor" (Eoghanachta), *84.Ailill "Oluimm" the 1st King of Munster.

Flatesbury or Flattesbere or Flatesbery or  Flattesberry. English origins. They were in Co. Dublin in the north - east of Southern Leinster and Co. Kildare in Central Southern Leinster in the early 14th Century AD.

O Flatley - Irish / Ua Flaithfhileadh. Later Ua Flaitile - flaith / prince - fhileadh / poet. A Heremonian Ui Cobhthaigh Dal Cuinn Ui Fiachrach Sept / Family branch, who had their territory in Co. Sligo in the north - west of the Connacht Province. Confused with O Flattery. Ancestors - *87.Fiachra the original 2nd King of Connacht (Ui Fiachrach), *88. Eochy "Mugmedon" the 124th King of Tara / Ireland, *80.Conn of the Hundred Battles the 110th King of Tara / Ireland (Dal Cuinn).

O Flattery - Irish / Ua Flaitre. A Heberian Dal gCais Ui Bloid Sept / Family branch - who had their territory in Co. Clare in the north - west of Thomond / Tuaiscert Mhumhain / Northern Munster who were the Dalcassian Chiefs of Fianchora with the O Cahills. Ancestors - *92.Blood / Blod (Ui Bloid), *91.Cas (Dal gCais) the King of Thomond, *37.Heber "Fionn" (Heberians).

O Flattery - Irish / Ua Flaithe. A Sept / Family branch who were the Chiefs of Lecale and the Kings of Ulidia, who had their territory in Co. Down in the south - east of the Ulster Province.

O Flattery - Irish / Ua Flaitre. A Sept / Family branch, who had their territory in Co. Offaly in the north - west of Southern Leinster.

O Flavelle - Irish / Ua Flannghail / Flannghaile. A Sept / Family branch, who had their territory in Co. Mayo in the mid - west of the Connacht Province. See also - O Flannelly.

Flavelle (of the yellow hair.) Anglo Norman origins / They were in the south of Co. Armagh in the south - east of the Ulster Province and surrounding regions.