Dozens of Holocaust survivors worldwide and their relatives are converging on a German courtroom Tuesday as the man known as the accountant of Auschwitz goes on trial. Oskar Groening, 93, a former bookkeeper and guard at the concentration camp, is accused of accessory to the murder of upward of 300,000 Jews who were killed there. Dozens of survivors or their relatives from the U.S., Israel, Canada and elsewhere have joined prosecutors as co-plaintiffs, and about half of them are expected in the German courtroom, 70 years after the camps were liberated by the Allies. Groening is accused of dealing with the belongings and money stolen from camp victims — the reason he's often called "the accountant of Auschwitz" in German news media. His is likely one of Germany's last Nazi trials, given the ages of those accused.