Poul Anderson 
The High Ones [EPUB ebook] 

After mutiny gives control of their starship to an enemy faction, the former crew can never return to Earth. Landing on the planet Novaya, they encounter hostile aliens mining rare minerals. Captured and imprisoned, three crew members uncover the truth about their civilization’s totalitarian decline into unthinking conformity. Their only hope to prevent the extermination of humanity lies in an impossible escape!