Originally, Bismark was known as Edwinton. The city was renamed after German Chancellor Otto Von Bismarck in 1873. The change was part of an attempt to prompt German investment in the Northern Pacific Railroad, which was attempting to construct a transcontinental railroad through the region.
The German money never came, but Otto Von Bismark did write a personal thank-you letter to the city. The discovery of gold in the Black Hills a few years later, however, turned the city into a major freight center overnight.