Belvedere House is a hunting lodge beautifully located beside Lough Ennell, 5km south of Mullingar, Co Westmeath. It was built for Robert Rochfort, Lord Belfield in 1740 from a design by Richard Cassels. The house was supposed to be a holiday retreat or villa, however, due to unexpected events that preceded its construction, it actually became a country house. In 1736 Robert Rochfort married Mary Molesworth. The couple were thought to be a great match and they had four children – three sons and a daughter. However, in 1743 Robert was informed of an alleged affair between Mary and his younger brother Arthur. At that point he moved from the family home at Gaulstown to the newly completed house of Belvedere, leaving his wife confined under house arrest at Gaulstown. He also pursued his brother Arthur forcing him to flee the country. George, the younger brother of Robert who made the initial allegation of the affair, later built much larger Tudenham mansion close to Belvedere House. This resulted in Robert building the Jealous Wall in 1760, so that he would not have to look at Tudenham mansion.
Richard Cassels, the architect who designed Belvedere House, was one of the greatest architects working in Ireland in the 18th century. The other famous buildings he designed are, among others, Russborough House in Co Wicklow, Powerscourt House in Co Wicklow, Westport House in Co Mayo, the Rotunda Hospital and Leinster House in Dublin.