The rise in antisemitic incidents across Europe has reached a new dimension through recent migration from predominantly Muslim countries. In public and media discourses, the role of imams and practicing Muslims has repeatedly come under scrutiny. This book explores the theological and historical foundations of Jewish–Muslim relations and examines attitudes shaped by Islamist thought toward Judaism, Jews, and the State of Israel. Using Austria as a case study, it presents qualitative interviews with 33 imams and 64 mosque attendees, whose statements are analyzed in accordance with the International Holocaust Remembrance Alliance (IHRA) Working Definition of Antisemitism.