In 2004, Yahad – In Unum was created to facilitate understanding and collaboration between Catholics and Jews. “Yahad – In Unum” is derived from the word “unity” in both Hebrew and Latin.

The founders of YIU were Cardinal -Jean Marie Lustiger, former archbishop of Paris, Cardinal Philippe Barbarin, archbishop of Lyon, Cardinal Jean -Pierre Ricard, archbishop of Bordeaux, Rabbi Israel Singer, former President of the World Jewish Congress, Mr. Serge Cwajgenbaum, secretary-general of the World Jewish Congress and Mr. Pinchas Shapiro.

Yahad – In Unum’s largest initiative is an ambitious, multi-year effort to systematically identify and document every single site of mass execution of Jews, Roma and other victims by the Nazis and their allies in Eastern Europe during World War II. The objectives are to substantiate this “Holocaust by bullets,” to irrevocably refute the Holocaust deniers of today and tomorrow, to serve as a permanent warning to humanity of the dangers of genocide and to allow for the respectful remembrance of the fallen.