A 'seminary for foreign missions' had been set up on rue du Bac in 1637 by Monseigneur Duval, with an accord from pope Urban VIII, during the Counter Reformation. The seminary's oratory or chapel was built between 1683 and 1689, with interior decoration by Jacques Stella, Nicolas Poussin and Simon Vouet, and it was this chapel that operated secretly as a parish church for the area during the Revolutionary era when the area's actual parish church of Saint-Sulpice was shut down. In 1801 the chapel was attached to the church of Saint-Thomas-d’Aquin, which became the church for the Faubourg Saint-Germain, and the 'Missions étrangères' parish was officially recognised and split from the parish of Saint-Sulpice in 1802, at which time its curé was abbé Dessaubaz.
40 years later, in 1842, the parish was dedicated to St Francis Xavier. However, the chapel soon became too cramped for the seminarians and parishioners to share and the parishioners began construction on a new church in 1861 under abbé Jean-Louis Roquette (curé of the church from 1848 to 1889), headed by Adrien Lusson then Joseph Uchard and paid for by the Ville de Paris. The chosen site was in the corner of boulevard des Invalides and a planned boulevard right across the district towards rue des Saints-Pères that would meet the Seine level with pont du Carrousel. According to the principals of Haussmann's renovation of Paris, the new church would then form the end to this planned boulevard, explaining why its siting seems odd today, shifted over the boulevard and the hôtel des Invalides. Lusson began the works, but they were interrupted in 1863 and resumed under Uchard after Lusson's death. Work on the exterior was completed on 15 July 1874 and inaugurated at Easter 1875, at which point the interior decor was still incomplete. It was finally consecrated on 23 May 1894, the eve of Corpus Christi, in a ceremony presided over by François-Marie-Benjamin Richard, archbishop of Paris.
References:The Clementinum is a historic complex of buildings in Prague. Until recently the complex hosted the National, University and Technical libraries, the City Library also being located nearby on Mariánské Náměstí. The Technical library and the Municipal library have moved to the Prague National Technical Library at Technická 6 since 2009. It is currently in use as the National Library of the Czech Republic.
Its history dates from the existence of a chapel dedicated to Saint Clement in the 11th century. A Dominican monastery was founded in the medieval period, which was transformed in 1556 to a Jesuit college. In 1622 the Jesuits transferred the library of Charles University to the Klementinum, and the college was merged with the University in 1654. The Jesuits remained until 1773, when the Klementinum was established as an observatory, library, and university by the Empress Maria Theresa of Austria.