An Prionsa Beag, in an Irish Celtic language used in Ireland.

Irish (Gaeilge) is a Goidelic language of the Insular Celtic branch of the Celtic language family. Irish originated on the island of Ireland and was the population’s first language until the late 18th century. Although English has been the first language of most residents of the island since the early 19th century, Irish is spoken as a first language in broad areas of counties Cork, Donegal, Galway, and Kerry, as well as smaller areas of counties Mayo, Meath, and Waterford. It is also spoken by a larger group of habitual but non-traditional speakers, mostly in urban areas where the majority are second-language speakers.

Irish used to be the dominant language of the Irish people, who took it with them to other regions such as Scotland and the Isle of Man, where Middle Irish gave rise to Scottish Gaelic and Manx. On the island, the language has three major dialects: Munster, Connacht and Ulster. All three have distinctions in their speech and orthography. There is also a “standard written form” devised by a parliamentary commission in the 1950s.

Irish has constitutional status as the national and first official language of the Republic of Ireland and is an officially recognised minority language in Northern Ireland. It is also among the official languages of the European Union. The modern-day areas of Ireland where Irish is still spoken daily as a first language are collectively known as the Gaeltacht.