In 1469 a group of Franciscans fleeing the Turks in Bosnia arrived in Novo mesto via Metlika, Bela Krajina, and in 1472 they built a monastery here. There was a fire in the monastery in 1664. At the end of the 15th century, the Franciscans in Novo mesto started collecting books in their library. The first known Franciscan librarian in Novo mesto is mentioned between 1735 and 1736 as Anton Kalan (Kallan, Khallan), formerly the Ljubljana and, after 1739, the Novo mesto guardian. From 1746 to 1870 the monks ran a grammar school (which proved to be an important educational platform for some eminent Slovenes) and from 1878 to 1919 an elementary school.
The Franciscan archives and library in Novo mesto today comprises 20,000 items, of which 7,000 items pre-date 1800 and are stored in the newer part of the library and an alleged 6,000 items of older material in the older part of the library. Besides books, including numerous precious incunabula, there are also manuscripts and archival records. The monastery also owns a number of oil paintings by Slovene baroque painter Valentin Metzinger, painted in 1726.