He was an Irish language writer during the Gaelic Revival. He wrote stories based on Irish folklore, some of the first Irish language plays, and regularly wrote articles in most of the Irish language newspapers such as An Claidheamh Soluis.
Cú Uladh was born in Allt an Iarainn, Co Donegal to Micheal McGinley and Susan Toner. He attended school locally until he was seventeen. He then attended Blackrock College in Dublin for two years. On leaving school he entered into the British Civil Service becoming an Inland revenue Officer. In 1895 he married Elizabeth Woods (Sibhéal Ní Uadhaigh) and they had twelve children. Cú Uladh spoke Irish from an early age and kept an interest in the language throughout his life, first publishing an Irish language short story and poem in The Donegal Christmas Annual 1883. It was not until 1895 while living in Belfast that he became involved in the Gaelic Movement.
It was in Cú Uladh’s Belfast home that the first meeting of the Ulster branch of the Conradh na Gaeilge in 1895. From this point on Cú Uladh became very involved in Conradh na Gaeilge becoming the organisations president on several occasions.
Cú Uladh was a member of Seanad Éireann from 1938–1942 when he was nominated by the Taoiseach Éamon de Valera.