Ardagh is a village in County Longford, Ireland. Ardagh is located towards the south of County Longford, 10 kilometres (6.2 mi) southwest of Longford town, located off the N4 road. Originally a site of pre-Christian worship, Ardagh became a site of Christian settlement with the arrival of Saint Patrick sometime between 434 and 435. The bulk of the village was laid-out in the mid-19th century. The barony of Ardagh is named for the village. There is a civil parish of Ardagh.