Stjepan Horvat (November 29, 1895 – March 12, 1985) was a Croatian patriot, geodesist and professor, dean of the Technical Faculty in Zagreb, head of the University of Zagreb, editor of the journals Geodetski list and Hrvatska državna izmjera, manager of the Department for State Survey in the Croatian Headquarters for Public Affairs, member of the State Land Consolidation Commission, colonel in the time of the Independent State of Croatia, adviser at the Military-Geography Institute in Argentina for 40 years and an honorary member of the Argentine Association of Geophysicists.
Horvat was born in Sremski Karlovci and he finished classical gymnasium in Vinkovci in 1915. He finished studies in geodesy at the University of Zagreb, where he later taught in the Technical Faculty. From 1944 to 1945 he was the university's rector.
In May, 1945 he escaped the communist regime in Yugoslavia with the fall of the Independent State of Croatia. He took the rector's chain with him on his departure from the country. He left the chain at the Pontifical Croatian College of St. Jerome in Rome for safekeeping during his time in Italy. The chain was originally a gift to the university by Emperor Franz Joseph I in 1877. Horvat emigrated to Argentina where he worked at the Institutio Geográfico Militar Argentino.
After the arrival, more than 50 scientific papers of him were published by the IGM, Argentine Association of Geophysicists and Geodesists, Pan-American Institute for Geography and History, and Direction for Geodesy of the Province of Buenos Aires, besides many other papers published in his mother country. Horvat's research interests chiefly deal with the adjustment computations of geodetic networks, general as well as geodetic cartography, ellipsoid geometry, and the development of feasible methods for automatic computation. Horvat is noted as the first person to use hyperbolic functions to ease and simplify problems of numeric calculations in the field of geodetic cartography.
Horvat is also noted as an amateur musician - he wrote Ave Maria, Adoration of the Lord (Croatian: Odanost Gospodinu), Ode to the Death (Croatian: Oda Smrti) and numerous other highly complex Croatian compositions which were performed by the choir Jadran he instituted in Argentina. To the honour of Croatian archbishop and martyr Alojzije Stepinac he composed a mass Beata Mariae Virginis. Mixed choir Jadran performed a concert in Rome in 1946 as Concerto di Musiche Nationali Croate, conducted by Horvat who for this occasion harmonised ten folk songs from Bosnia—Dalla fiera Bosnia, and six folk songs from his native Srijem—I souni dell Oriente Croato. That concert received praise by music critics and was taped to a gramophone record.
He died in Buenos Aires on March 12, 1985 and was buried there. Argentine Association of Geophysicists and Geodesists proclaims him honorary member in 1979. During the 22nd Conference of Geophysicists and Geodesists held in Buenos Aires 6–11 September 2004, a memorial plate to Stjepan Horvat was revealed in the entrance space of the Military-Geography institute.
With democratic changes in Croatia in 1991, the Pontifical Croatian College of St. Jerome returned Horvat's chain to the university. The university rehabilitated Horvat from the Communist period and restored his rector's picture on November 3, 1994.