The story of the Liebfrauenkirche began with Emperor Constantine the Great. At the time of the 20th anniversary of his reign in the year 326, he had churches built in the most important places of Christendom: it was his initiative that led to the building of the old St Peter's Basilica and the Lateran Basilica in Rome, the Church of the Holy Sepulchre in Jerusalem, the Church of the Nativity in Bethlehem, the Church of the Holy Apostles in Istanbul and also the double church in Trier, which was the largest church in the Imperium Romanum. The city was severely damaged during attacks by the Franconians, but Bishop Nicetius was able to have the double church restored again. The situation was different after the dreadful storming of Trier by the Normans in 882, when its churches fell together with the ancient city. Under Bishop Ruotbert (931–956) the southern church was rebuilt in the Ottonian style as the Marienkirche (Church of Our Lady).
A Gothic reconstruction of the Liebfrauenkirche came about when builders from the Île de France and Champagne (Rheims) came to Trier, and suggested to Archbishop Theoderich II that he should have a new church in the modern High Gothic style erected on the site of the now derelict Marienkirche. What they proposed promised to be so breathtakingly beautiful that the Archbishop agreed.
And indeed, after a construction period lasting 33 years (1227–1260) a central church stood on the south side of the cathedral, built on the outline of a twelve-petalled rose (rosa mystica) in the finest French High Gothic filigree architecture. Like its predecessor, it was consecrated to the mother of God. It celebrates its consecration festival on 15 August.
In 1951 the Liebfrauenkirche was elevated to a papal minor basilica, and together with the Dom it has been on the UNESCO World Cultural Heritage list since 1986. The last extensive internal renovation took place from 2007 – 2011.
Guided tours are possible subject to prior reservation at the Dom information office. Sightseeing visits are only possible when services are not being held.