here’s a stirring rock song about Nachtigall, by the first Ukrainian folk rock outfit of Glasnost’:

OUN formed two divisions, the Nachtigall and Roland battalions, that operated under the German Abwehr command.

But after two years of brutal German rule, they formed the Ukrainian Insurgent Army (UPA), which declared itself to be against both the Nazis and Soviets. (UPA was led by Roman Shukhevych, who led the S.S. Nachtigall unit).