This is the grandest room of the State Apartments, and contains one of the most important decorative interiors in Ireland. Formerly the ballroom of the Lord Lieutenant's administration, today the room is used for presidential inaugurations. It is one of the oldest rooms in the castle, dating from the 1740s, though its decoration largely dates from c. 1790, including the most significant painted ceiling in Ireland executed by Vincenzo Valdre (c. 1742–1814). Composed of three panels, the ceiling depicts the coronation of King George III, Saint Patrickintroducing Christianity to Ireland, and King Henry II receiving the submission of the Irish Chieftains. The state dinner hosted by the President of Ireland to welcome Queen Elizabeth II to Ireland was held here on the evening of 18 May 2011.