The Sioux Spaceman — Andre Norton

Kade Whitehawk is a rebellious junior member of the Terran Space Service, an organization involved in intergalactic trade. The background of this science fiction novel is a little different from the author's usual universe of Free Traders and long-vanished Forerunners.

Here, the Terrans are newcomers to the stars where the humanoid Styor lords still rule a decaying galactic empire. Kade despises the Styor for their arrogant belief that all other races are little more than animals or slaves. On his first outbound mission, he tangles with a Styor lord and is bundled back to the Traders' Base on Lodi in disgrace.