Complex sentence: As leader of the Bielski partisans, his aim was not to attack railroads and roads that the German Nazis were using as supply routes, although some of these attacks were made in order to save Jews, who were under persecution from the Nazis in the Holocaust.
Split into simpler sentences: As leader of the Bielski partisans, his aim was not to attack railroads and roads that the German Nazis were using as supply routes. Although there were made some of these attacks in order to save Jews, who were under persecution from the Nazis during the Holocaust.