In Irish mythology Cearmna Finn was joint High King of Ireland with his brother Sobhairce. Sobhairce ruled the northern half and Cearmna the south. They were the first High Kings of Ireland to come from the Ulaid.
Their reign lasted 40 years. Cearmna was killed by Eochaid Faebar Glas, son of Conmael. Sobhairce was killed by Eochaid Mann of the Fomorians.