Fedlim Geancach Ó Conchobair (Feidhlimidh Gheangcaigh mac Toirdhealbhaigh Óig Ó Conchobhair Donn) (died 1475) was an Irish monarch of the fifteenth century. He was one of the sons of Toirdhealbhach Óg Donn Ó Conchobair and King of Connacht from 1461–1475. Fedlim Geancach Ó Conchobair succeeded to the throne of the Connachta in 1461 after the death of Aedh mac Tairdelbach Óg Ó Conchobair. Fedlim was the last fully recognized monarch of The Kingdom of Connacht.
Cathal mac Ruaidri Ó Conchobair was a King of Connacht and the son of Aedh mac Tairdelbach Ó Conchobair. Few single members of the Ó Conchobair dynasty were able to assume overall control of the three main clan septs after the 1380s. Toirdhealbhach was one of the very last of the kings, who were by now reduced to their ancestral lands in County Roscommon.
The Connachta are a group of medieval Irish dynasties who claimed descent from the legendary High King Conn Cétchathach. The modern western province of Connacht takes its name from them, although the territories of the Connachta also included at various times parts of southern and western Ulster and northern Leinster. Their traditional capital was Cruachan.
Aedh mac Tairdelbach Óg Ó Conchobair, was one of the sons of Toirdhealbhach Óg Donn Ó Conchobair and King of Connacht from 1439–1461. Aedh Ó Conchobair succeeded to the throne of the Connachta in 1439 after the death of Cathal mac Ruaidri Ó Conchobair and was succeeded by Fedlim Ó Conchobair, also a son of Toirdhealbhach Óg Donn Ó Conchobair.
