"A House of God, of whatever religion, is a holy place," he said. "An attack on a House of God of any religion constitutes an attack on all religious communities."
In October 1943 homily, the archbishop condemned notions of racial superiority.
"The Catholic Church knows nothing of races born to rule and born to slavery," he said. "The Catholic Church knows races and nations only as creatures of God."
The Ustashe lost control to Marshal Tito's communists partisans, who had used Stepinac's anti-Ustashe comments in their propaganda. Yugoslavia's communists then turned on Archbishop Stepinac.
In 1946, Stepinac was put on trial for allegedly collaborating with the Ustashe's crimes. The trial drew critical coverage from Western media like Time and Newsweek and protests from those who saw it as a show trial.
Among the trial's critics was the American Jewish community leader Louis Breier, who organized protests in New York City in support of the archbishop.
Archbishop Stepinac was denied effective representation and only met with his attorney for an hour before the trial. The government's witnesses were told what to say, and the archbishop was not allowed to cross-examine them.
What you have is a false narrative created by Soviet agents.
He was sentenced to hard labor, but after a global outcry his sentence was reduced to house arrest.
"Nevertheless, it becomes the public record that he was convicted of collaboration," Rychlak said.
Rychlak sees the trial and its aftermath as part of the same propaganda campaign that would target Pope Pius XII, Hungary's Cardinal Jozsef Mindszenty and other Eastern Bloc churchmen with claims of Nazi collaboration.
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"What you have is a false narrative created by Soviet agents," Rychlak said. "The directive would have come from the Kremlin."
A communist-made movie circulated throughout Yugoslavia used footage of the archbishop's trial in a misleading way.
At the trial, Archbishop Stepinac began his 18-minute criticism of the trial's legitimacy with the phrase "I will not defend myself against these charges." The movie only showed this first phrase, and not the archbishop's lengthy criticism.
In the early 1960s, the Italian writer Carlo Falconi sought the records of the Stepinac trial from the Yugoslavian government. Rychlak said the government's records show a "frantic rush" to respond.
"If they turn over the files as they existed, it would be clear that it's a sham. They fabricate some documents, cherry-pick some documents, and send him some files," the professor said.
Falconi's book and its strong criticism of Stepinac then became a foundational text in criticisms of Pius XII's wartime record.