Drago Pilsel was born in Buenos Aires, Argentina to a politically engaged family. His parents were Croatian immigrants who came to Argentina as children after World War II. Pilsel's grandfather from his father's side was an Ustaše collaborator. Pilsel's father, Adolf Pilsel was a member of the fascist organization called Croatian Liberation Movement. He was also a bodyguard to Ante Pavelić at some time.
Drago Pilsel spent his childhood in Comodoro Rivadavia where his father worked in construction. After financial troubles emerged, they moved back to Buenos Aires. His father was forced to leave him and his mother after some time and move to Paraguay.
Pilsel spent his high school years during the National Reorganization Process. He became then introduced to humans rights and journalism. In 1979, he returned to Comodoro Rivadavia for a year and started working on a TV station called Channel 9. In Buenos Aires, he graduated from the high school specialized for mechanics and started working in construction. He was also a dedicated Croatian nationalist. He regularly sprayed graffiti against Yugoslavia and spread hate against it. Once he also broke a window of a synagogue. After spending some time in São Paulo with his girlfriend in the 1980s, he became interested in the Franciscan order. He returned to Argentina and enrolled in that order. It was at that time when he rejected nationalism.
In 1989, he came to Zagreb in Yugoslavia for the first time in his life as a Franciscan. He was sent to Dalmatia for some time to learn and in 1991 he went to Rijeka to study in the Roman Catholic Archdiocese.
He left the Franciscan order in September 1991 after his brother was pronounced missing during the Croatian War of Independence. Pilsel immediately enlisted in the Croatian army and served under the future Croatian minister of defense Ante Kotromanović in Dalmatia. He left the army in 1992. In March 1992, he went to study philosophy and theology at the Catholic Faculty of Theology in Zagreb. He gave his final examinations there but ultimately graduated from the Evangelical theology faculty in Osijek.