Cardinal Wuerl blessed the dome with incense during Mass for the feast of the Immaculate Conception. Cardinal Kevin Farrell, prefect of the Dicastery for the Laity, Family and Life attended the dedication as an envoy on behalf of Pope Francis and presented the cardinal and the rector of the Basilica, Msgr. Walter Rossi, with a letter of Apostolic Blessing from the Pope for the blessing.
The new dome and its mosaic, which depicts the Trinity, Mary, and nearly twenty saints and blessed who share a connection with either the Americas or the National Shrine itself, is the capstone which finishes 97 years of construction and decoration of the Basilica and its interior. Five cardinals, 23 bishops, nearly 90 priests, and over 4,000 people gathered to celebrate the event. Also present at the event were Cardinal Daniel DiNardo of Galveston-Houston, president of the U.S. Conference of Catholic Bishops, and U.S. Ambassador to the Vatican Callista Gingrich.
The construction of a National Shrine to Our Lady of the Immaculate Conception was announced in 1918 and construction began in 1920. "People were invited all over the country to contribute in whatever way they could," Cardinal Wuerl explained, and "some donated some pieces of old jewelry and others donated some precious stones."
After the completion of the Crypt Church in 1931, construction on the Upper Church was paused for the Great Depression and World War II, but resumed in 1945. The Church's structure was completed in 1959.