The event was organised by the University of Zagreb Faculty of Divinity.
Zagreb Archbishop Cardinal Josip Bozanic spoke, among other things, about the significance of the anniversary.
Speeches were also delivered by representatives of other Christian churches and religions, including Mufti Sevko Omerbasic of the Islamic community, representatives of the Science and Education Ministry and the University of Zagreb, and Mayor Vlasta Pavic.
A telegram was sent to the pope. Attending today's opening were also the Apostolic Nuncio to Croatia, Javier Lozano, Sarajevo Archbishop Cardinal Vinko Puljic, Banja Luka Bishop Franjo Komarica, and numerous religious dignitaries from Croatia and neighbouring countries.