Purim celebrates the triumph over Haman, a Persian landlord who intended to kill the Jews of ancient Persia (modern day Iran).  The Biblical story is told in the Book of Esther (known as the Megilla) and is read during the celebration.  According to the story, Queen Esther (a Jew herself) intervened and prevented Haman from implementing his plan. Jews use groggers (handheld rattles) to express joy and merriment during Purim, and to block out the sound of Haman’s name as the Megillah is read.  Hitler was in many ways a modern-day Haman, and so the Book of Esther and the festival of Purim took on special significance to Jews during the Holocaust.