The Church of St. Jacob was first mentioned in 1155 as chapel under the administration of the Cathedral of Constance. The combined bell tower and choir was probably build in the 13th or 14th century. In 1465 the nave was extended toward the west and the tower was raised. The sacristy was added in 1489, bringing the church to its current appearance. In the same year it was raised to a parish church and the center of a local parish.
The baptismal font was added in 1590. The pulpit was built in 1790. The sundial was painted in 1808 by Conrad Boltshauser and restored in 1954. During a renovation in 1975, two frescos were discovered. The Weihnachtsgeschichte or Christmas Story was painted in the 15th century, while the Last Judgement is from around 1460-70. The church is shared between the Reformed and Roman Catholic residents.
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.