Buchenwald, BOO kuhn vahlt, was a concentration camp in Nazi Germany. The Nazis built the camp between 1935 and 1937 near the city of Weimar. People held at Buchenwald included political prisoners and such ethnic prisoners as Jews and Poles. About 57,000 of the prisoners were murdered by the Nazis or died from such causes as starvation and disease. Many of those who died were worked to death in Nazi-controlled factories surrounding the camp. The United States Army freed the surviving prisoners in April 1945.