Some have accused him of being Hitler’s pope. The decision to open the archives will show if he was guilty of something more than indifference

Compared with other popes, Pius XII was not an egregiously wicked man. He neither enriched nor enlarged his family. He burnt no heretics and started no wars. But he was – unremarkably so by the standards of his time and class – antisemitic. He was also a contemporary of Adolf Hitler’s, and one who occupied a position of considerable moral authority.

The historical record shows Pius did very little to condemn the Holocaust, and nothing effectual to stop it. He was the Vatican’s chief diplomat before becoming pope in 1939. He held the office all through the second world war and the first decade of the cold war. Since his death he has been accused of crimes ranging from active collaboration with the Nazis to passive acquiescence in their crimes and indifference to the suffering of their victims. It is also charged against him that he dissolved the Catholic lay party in Germany, when that party might have been a bulwark against Hitler’s rise.

Some German Catholics, including some he personally tried to help, did risk and even lost their lives in the struggle against fascism. Most did not. All these claims have been fought over by historians for decades. But their arguments have been hampered by the fact that the relevant Vatican archives were mostly closed to scholars. Now they are all to be opened, after 30 years of pressure. “The church loves history,” said Pope Francis, announcing the move. The question is whether history will love his church.

The charge against Pius of active collaboration is certainly unfounded. There were some parts of the Catholic church in eastern Europe which went along enthusiastically with the fascist programme, as the church had also done in the Spanish civil war. In all these cases, Christians believed they were defending themselves, and their societies, against Stalinism. Pius was ferociously anti-communist, but he balked at the planned extermination of the Jewish people.

His defenders argue that he did what he could within the constraints of his powers. That may be true. If so, that gives his case a tragic aspect. Popes cannot, like Jesus, renounce all power to save others. As heads of a vast multinational organisation, they must exercise their power in the world, compromising with others, sometimes with evil regimes. Whether they choose unyielding defiance, or supple accommodation, innocents will suffer.

Pope Francis himself had to deal with the military dictatorship in Argentina, and now with the Chinese police state. His compromises in both situations can be criticised. But great moral choices are always easier to make when seen from a safe distance. Those who rush to condemn Pope Pius today might ask themselves how history will judge the British government which chooses to sell arms to Saudi Arabia in its murderous and unjustified war in Yemen. Perhaps the civilian victims of that war seem as the Jews of Europe seemed to Pope Pius, not really quite as human or as valuable as other people.