The book explores several key themes:
* The impact of the Carlisle Indian School: It was a place of both opportunity and oppression, attempting to assimilate Native American children into white society while stripping them of their cultural identity.
* Jim Thorpe's athletic prowess and the challenges he faced: Sheinkin portrays Thorpe as a remarkable athlete, but also explores the racism and prejudice he encountered in his journey to becoming a global icon.
* The legacy of Jim Thorpe's accomplishments: Thorpe's Olympic victory was a source of pride for Native Americans but also a reminder of the injustices they faced.
* The broader struggle for Native American rights: The book contextualizes Thorpe's story within the larger context of the fight for Native American sovereignty, cultural preservation, and self-determination.
Ultimately, "Undefeated" is a powerful and nuanced exploration of the life and legacy of Jim Thorpe, as well as the complexities of race, identity, and the impact of colonialism on Native American communities.