ROME — After more than three decades of pressure from historians and Jewish organizations, Pope Francis announced on Monday that he would open the sealed archives from the World War II-era pontificate of Pius XII, allowing scholars to examine how the Vatican responded to Nazism and the Holocaust.

Some critics of Pius XII maintain that he was shamefully silent during the Nazi massacre of Jews during the war, while others claim he saved thousands of lives by ordering the Roman Catholic Church to assist victims of persecution.

“The church is not afraid of history,” Francis told officials and staff members of the Vatican Secret Archives, the papal repository that contains tens of thousands of documents related to Pius XII.

Francis said that Pius’s pontificate, which stretched from 1939 to 1958, had included “moments of serious difficulties, of tormented decisions, of human and Christian prudence.”