Josip Juraj Strossmayer was born in Osijek on February 4, 1815, to father Ivan and mother Ana, born Erdeljac He completed six classes of the Franciscan high school in Osijek, and then continued his education at the Catholic school in Đakovo. After completing the second year of philosophy studies, he was sent to the central Catholic school in Pest, where he studied theology. He received his doctorate in philosophy on October 24, 1837. He was ordained a priest on February 16, 1838 in Đakovo. For two years he was a chaplain in Petovaradin in the monastery of St. George, and after that he went to Vienna as a student of the Augustinum of the University of Vienna. He received his doctorate in theology from the University of Vienna in 1842. After returning to Đakovo, he was appointed a professor in a Catholic school (he taught philosophy, mathematics, world history and biblical studies). He successfully taught canon law at the University of Vienna. On the recommendation of the then Bishop Kuković, and with the consent of Ban Jelačić, he was appointed Bishop of Đakovo on November 18, 1849. The appointment found him in Đakovo, where he was appointed bishop on September 8, 1850. years. The ceremonial inauguration and taking over of the diocese took place in Đakovo on September 29, 1850. Bishop Strossmayer ruled the diocese for fifty-five years. In the period from 1866 to 1882, he built the Đakovo church, today’s cathedral.
He participated in the First Vatican Council from 1869 to 1870. Assisted in founding the Academy of Sciences and Arts in Zagreb in 1868. In 1873, he started the diocese’s newsletter, the Gazetteer of the Diocese of Đakovo and Srem. In his time, in 1880, the bishop’s printing house was opened, which developed a rich publishing activity. He donated his precious collection of paintings and works of art to the gallery of paintings in Zagreb, which was officially opened in 1884.
Strossmayer participated actively in political, educational, cultural and charity work.
Bishop Strossmayer died in Đakovo on April 8, 1905 at the age of 91. He was buried in the crypt of the Đakovo Cathedral.