By Blood chronicles American Indians of African descent as they battle to regain their tribal citizenship. The film explores the impact of this battle, which has manifested into a broader conflict about race, identity, and the sovereign rights of indigenous people. The film demonstrates both sides of the battle, the shared emotional impact of the issue, and the rising urgency of the debate: a Native American and African American history has been overlooked, and a tribal body feels as though their sovereignty is under siege.