In this small town on the left bank of the Una at the foot of the hill called Djed, the Franciscans also lived in pre-Turkish times, from the middle of the 14th century. They were patronized by the lords of the town, in the 15th century Frankopani, and in the 16th century Zrinski, until 1556 when the town was conquered by the Turks.
– In 1690, the Franciscans return to Kostajnica. After the Christian army liberated the city in 1688, ban Nikola Erdõdy enabled Fr Pacifik Dolovščak to build the ancient monastery and the ancient church of St. Anton. The Franciscans established a parish in Kostajnica and in the neighboring towns of Zrin and Sunja. In 1706, Bishop Martin Brajković took over the Kostajnica parish and handed it over to the secular clergy
– 1694, on May 20, Friar Ladislav Horvat was killed as a martyr of the Christian faith by the Turks; the Turkish army executed him on the other bank of the Una
– In 1720, on the ruins of the medieval monastery, the Franciscans built the chapel of St. Anne; they placed the altar of St. Franje so that their former place of residence does not fall into oblivion
– In 1726, preparations for the construction of a brick church began; from 1729 to 1735, the construction was led by Friar Dionizije Bizančić with the help of Ban Ivan Pálffy; the works were completed in 1746 by brother Bernardo Lacković
– In 1751, the construction of a new monastery began, and that of the part that adjoins the sacristy of the church
– In 1753, the altars of St. Anthony, St. Barbara and St. Francis; those altars as well as the pulpit were gilded and marbled in 1764 by the Franciscan painters Lazar Cvek and Luka Auleidner
– In 1764, the construction of the church tower began; it was completed in 1779 by Friar Venancije Turek
– In 1765, Fr. Anđeo Novosel led the Fraternity of the Scapular, and the Fraternity of the Franciscan Belt was already active earlier.
– In 1779, the Franciscans were teachers at the so-called normal school; Fr. Baltazar Vrbančić was first mentioned as a teacher in 1742; In 1793, lay teachers took over teaching positions, but from 1789 to 1873, the school had its classrooms in the monastery.
– In 1790, the state authorities abolished the monastery, but the decision was not implemented; it was revoked only in 1801
– In 1794, the Kostajnica Franciscans led the parishes in Hrastovica, Krapje and Lonja, and acted as chaplains in Sunja, Kalnik, Marija Gorica and Lipovljani; after 1804 they returned to the monastery
– In 1797, the current organ was acquired; they are the work of Antun Scholz
– in 1885, the bishop of Banja Luka, Friar Marijan Marković, handed over the leadership of the parish in Bosanska Kostajnica to the monastery; in the Dobrljin branch in 1933, the church of St. Križa, in 1972 the bishop entrusted that parish to the secular clergy
– In 1890, the bell tower of the church was restored with the help of the City Administration after it was damaged by a lightning strike
- during II. during World War II, the bell tower was the target of bombing by the army of the old Yugoslavia from Bosnia, as well as the target of allied bombing; it was restored only at the beginning of the fifties
– In 1991, after the occupation of Hrvatska Kostajnica, the Serbs looted and burned the monastery and the church and blew up the belfry
- since 1995, the citizens of Hrvatska Kostajnica, in the organization of the city authorities and with the help of good people from various associations of the city of Zagreb, have been cleaning the ruins of the monastery and the church
– In 1996, the Franciscans took over the parish of St. Nicholas the Bishop, the restoration of the church and monastery begins
- from 1996 to 1998, masses were held in the temporary parish office in the Maraković house
– In 1998, the city council of Hrvatska Kostajnica declared June 13, the holiday of St. Anthony of Padua, for City Day
– In 1998, the city administration presented the monastery with a silver cross
- In 1999, the city council awarded Fr. Antun Hajmiler the highest city award "Charter of the City" for his special merits in the return of life and spiritual renewal of the city on the occasion of the City Day.
– June 13, 2000, St. Mass on the occasion of the feast of St. Anthony and City Day was led by Zagreb Archbishop Josip Bozanić
– On July 20, 2000, the new bell was consecrated
Today's scope of activity of the monastery in Kostajnica includes the proclamation and sharing of sacraments in the monastery church, pastoral assistance to nearby parishes, and preservation of the cultural legacy created by the activities of the church and monastery.