Final answer:
Elie and the other prisoners were sent on a death march as they were evacuated from the camp to cover up the Holocaust's atrocities before the Allies could discover them.
Step-by-step explanation:
The reason Elie and the other prisoners were sent on a march into the night was because they had been evacuated from the camp. In early 1945, with the Allies closing in from both the east and the west, the Nazis initiated a series of death marches from the camps in Poland to transport the remaining Jewish prisoners. Prisoners were forced to march through harsh conditions, then loaded into cattle cars and sent deeper into Germany. The goal was to move them away from the advancing liberating forces and to cover up the evidence of the Holocaust's atrocities before the Allies could witness them. This evacuation attempt was due to the fear of what Allied soldiers might discover, which included the unspeakable conditions and the emaciated survivors of the camps.