A searing account of the French Catholic Church’s complicity in the Holocaust, revealing how the nation’s most influential bishops shaped the course of Nazi persecution through closed-door negotiations and hollow promises. When German occupiers rolled into Paris in June 1940, they arrived wary of the French Catholic Church. In a country where more than 80 percent of citizens were Catholic, bishops held enormous moral sway. During the 1930s, many used their positions to forcefully condemn the rise of Nazism. But as the persecution of Jews escalated during the Occupation, every bishop in France maintained a deafening silence. In fact, the Church stood publicly alongside Marshal Pétain’s collaborationist Vichy regime. Even when bishops famously broke silence to protest the deportation of Jews in 1942—a moment long remembered as one of moral awakening—they quickly retreated, discouraging further defiance. The French Church’s public silence during the Holocaust is no secret. But as Aliza Luft shows, private interactions between bishops, French Jewish leaders, and Vichy officials were just as consequential. Turning to letters, diaries, and records of private conversations, Luft traces the moral dilemmas and calculated choices that shaped these hidden negotiations. As Jewish leaders turned to the Church for information and protection, bishops repeatedly assured them of the Church’s sympathy and support. These guarantees from the nation’s highest moral authorities, combined with the false promises of Vichy officials, encouraged French Jews to place their faith in relationships and republican ideals that proved tragically hollow. Drawing on years of archival research, Sacred Betrayal is a harrowing account of how genocide unfolds day by day—not only through spectacular violence, but also through misleading assurances, quiet capitulations, and broken promises.