Cathal is a common given name in Ireland. The name is derived from two Celtic elements: the first, cath, means "battle"; the second element, val, means "rule". There is no feminine form of Cathal. The Gaelic name has several anglicised forms, such as Cathel, Cahal, Cahill and Kathel. It has also been anglicised as Charles, although this name is of an entirely different origin as it is derived from a Germanic element, karl, meaning "free man".
As is evident from the list below, the name was, in medieval times, most popular in Ireland's two western provinces, Munster and Connacht.
Cathal Hayden, Northern Irish fiddle and banjo player of note.
Cathal Magee (born 1954), Chief Executive Officer of the Health Service Executive (HSE) in Ireland (2010–2012)
Cathal Mannion (born 1994), Irish hurler who plays for Galway Senior Championship
Cathal Mac Coille (born 1952), retired Irish broadcaster, researcher and journalist
Cathal MacSwiney Brugha (born 1949), Irish decision scientist, the Emeritus Professor of Decision Analytics at University College Dublin's College of Business