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Anno a Christo Nato MDCCCVII
The Chapel Royal in Dublin Castle was the official Church of Ireland chapel of the Household of the Lord Lieutenant of Ireland from 1814 until the creation of the Irish Free State in 1922 when the office of Lord Lieutenant, and his British government regime in Ireland was terminated.
The chapel was designed by Francis Johnston and contains one of the finest Gothic revival interiors in Ireland. It was built to replace an earlier 18th century church that suffered structural problems due to being built on soft ground close to the site of the original castle moat. The new Chapel Royal was built using a timber frame to make it as light as possible, but still it took seven years to build due to the difficulties relating to the site and also because of the "sheer opulence" of the interior.
Building started on 15 February 1807 and the chapel was opened, behind schedule and over budget, on Christmas Day, 1814. Charles Whitworth, 1st Earl Whitworth and Lord-Lieutenant contributed the centre portion of the large stained-glass window above the altar, which reputedly had come from Russia.
The decoration of the ceiling of the interior was done by George Stapleton while sculptor Edward Smyth and his son John (responsible for the statues on the General Post Office) carved the larger figures. Over the chancel window are three life-size figures representing Faith, Hope and Charity. Over the galleries are heads representing Piety and Devotion.
The exterior features over 90 carved heads, including those of Brian Boru, St. Patrick, Archbishop Ussher and Jonathan Swift, done by Edward and John Smyth.
The large organ in the chapel, still playable, is said to have been a gift from Prince Albert, consort of Queen Victoria.
In 1943, the church became the property of the Irish Army, and the former Church of Ireland chapel became a Roman Catholic Church, under the name the Church of the Most Holy Trinity. The Stations of the Cross were then carved by the monks in Glenstall Abbey and presented to the church in 1946. Although the chapel has not been deconsecrated, neither Masses nor Divine Services take place there any more.