The film is based on the true story of Father Jerzy Popieluszko, a Catholic priest and Solidarity supporter who was murdered by agents of the Polish secret police.
To prepare for his role, Christopher Lambert spent hours watching the sermons of Father Jerzy Popieluszko. Lambert realized that the most important aspect of Popieluszko wasn't his sermons, but the reaction from his crowds, who - according to Lambert - treated Popieluszko more like a rock star than a priest.
One of three movies starring Ed Harris and directed by Agnieszka Holland, with the other two films being Au coeur du miracle (1999) and Copying Beethoven (2006).
Richard Dreyfuss was the original choice of the Ed Harris part.
Three members of the cast portrayed famous painters in biopics: Tim Roth played Vincent Van Gogh in Vincent et Théo (1990), Ed Harris played Jackson Pollock in Pollock (2000), Timothy Spall portrayed JMW Turner in Mr. Turner (2014).