Catherine of Bosnia, also known as Katarina Kosača-Kotromanić, was born about 1424 or late August 1425, daughter of Stjepan Vukčić Kosača, Grand Duke of Bosnia and later Herzegovina, and Jelena Balšić. She was raised in her father's adherence to the Bosnian Church, though her mother was Eastern Orthodox. Little is recorded of her childhood beyond a bequest of gold earrings and a snake-shaped bracelet in the 1442 will of her maternal great-grandmother.
After King Stephen Thomas converted to Roman Catholicism and obtained papal permission to set aside his earlier union, peace with the powerful Kosača family was sealed by Catherine's marriage. Between 19 and 22 May 1446 she was wed to the king according to the Catholic rite at Milodraž near Fojnica. At that time she herself laid aside the errors of the Bosnian Church and embraced the Catholic faith with zeal. Pope Eugene IV allowed her to choose two Franciscan chaplains. As queen she devoted her dowry to the energetic building of churches throughout Bosnia: at Kupres in 1447, Krupa na Vrbasu, Jezero, and in 1458 a church and Franciscan monastery at Jajce that she asked Pope Pius II to dedicate to her patroness, Saint Catherine of Alexandria. The pope granted indulgences to pilgrims who visited it. Other churches at Vrbanja, Vranduk, Tešanj, and Vrila are likewise linked to her patronage. She bore the king at least two children: Sigismund (born c. 1449) and a daughter Catherine (born 1453).
King Thomas died in the summer of 1461. Catherine, then about thirty-seven, became queen dowager at the court of her stepson Stephen Tomašević, who guaranteed her rank and privileges. In the spring of 1463 Sultan Mehmed the Conqueror invaded Bosnia. The royal family scattered; Catherine was besieged in Kozograd while her children were seized at Zvečaj and carried to Constantinople, where they later embraced Islam. Her stepson was executed. Defying the order to surrender, the defenders of Kozograd enabled the queen to escape. She reached the coast, sailed to Ragusan territory, and after temporary refuge in Dubrovnik and elsewhere finally crossed to Italy in 1467, landing at Ancona and settling in Rome under a generous papal pension.
In Rome she lived with a retinue of Bosnian nobles, first near San Marco and later with property granted by Pope Sixtus IV beside the Tiber. She appeared at notable ceremonies, including the proxy wedding of Ivan III of Russia and Sophia Palaiologina, and made pilgrimages, once accompanied by forty mounted knights. Yet her heart remained fixed on her captive children. She sought the mediation of Italian princes and in 1474 even traveled to Novi in her family's lands, hoping through her half-brother, now an Ottoman statesman, to open negotiations. All efforts failed; both children remained Muslim.
Disappointed, she returned to Rome and entered the Secular Franciscan Order, inspired by the friars of Santa Maria in Ara Coeli. Shortly before her death the Hungarian puppet king Nicholas of Ilok pressed her to recognize his claim; the ailing queen answered with such fury that she "looked like a sharp sabre." On 20 October 1478 she made her last will before Franciscan witnesses, asking burial before the high altar of Ara Coeli, naming the pope and his successors guardians of the Bosnian crown until her son or daughter should return to the Christian faith, and disposing of sacred objects and her husband's silver sword. She died five days later, on 25 October 1478. Her bilingual Latin and Bosnian epitaph was later recorded; she rests in Ara Coeli.
From the Franciscan province of Bosna Argentina under Ottoman rule she came to be venerated as a symbol of Bosnia's Catholic past and enduring hope. She was noted as beatified in the Martyrologium franciscanum of 1638 and remains dear to the Catholics of Bosnia and Herzegovina.
May Blessed Catherine intercede for us, that we may persevere in faith and entrust those we love to God's mercy.
