Stjepan Razum is a Croatian church historian and Roman Catholic priest. He is the director of the Archdiocesan Archives in Zagreb and a member of the Commission for the Croat martyrology of the Episcopal Conference of Bosnia and Herzegovina and Episcopal Conference of Croatia; mainly researching on the Catholic priests and nuns killed and persecuted by Yugoslav communists.^[3]

In addition, Razum strongly believes and advertises that the Earth is flat.^[4]

Razum is also the president of Society for Research of the Threefold Jasenovac Camp ("Društvo za istraživanje trostrukog logora Jasenovac"); he and the secretary of that society popular historian Igor Vukić were both publicly denounced as Holocaust deniers.^[5]

In 2018, Razum published a Facebook post expressing support for Richard Williamson, a member of a fringe Catholic breakaway movement who was convicted of Holocaust denial in Germany.^{[6][7][8][9][10][11]}

In January 2019, Razum and Croatian mathematician Josip Pečarić published a book titled Razotkrivena jasenovačka laž ("The Jasenovac Lie Revealed"), which denies that the Ustaše operated an extermination camp at Jasenovac, arguing instead that it was a forced labor camp.^[12]