County Waterford is a county in Ireland. It is in the province of Munster and is part of the Southern Region. It is named after the city of Waterford. Waterford City and County Council is the local authority for the county. The population of the county at large, including the city, was 127,363 according to the 2022 census. The county is based on the historic Gaelic territory of the Déise. There is an Irish-speaking area, Gaeltacht na nDéise, in the southwest of the county.

Irish, also known as Irish Gaelic or simply Gaelic, is a Goidelic language of the Insular Celtic branch of the Celtic language group, which is a part of the Indo-European language family. Irish is indigenous to the island of Ireland and was the population's first language until the 19th century, when English gradually became dominant, particularly in the last decades of the century. Today, Irish is still commonly spoken as a first language in areas of Ireland collectively known as the Gaeltacht, in which only 2% of Ireland's population lived in 2022.