Final answer:
Interior peoples were regarded as less civilized due to historical stereotypes like primitivism and orientalism, which depicted non-European cultures as less advanced. These stereotypes justified colonial ambitions and the mistreatment of Native American and African societies, despite evidence contradicting these prejudices.
Step-by-step explanation:
The notion that interior peoples were regarded as less civilized has its roots in historical biases and stereotypes, such as primitivism and orientalism. European and Euro-American cultures were often seen as the pinnacle of civilization, using these bias-based scales to rank other cultures as less developed.
Stereotypes constructed by these cultures often depicted Native American and African societies as primitive or noble savages, without the civilized characteristics attributed to Europeans. These stereotypes were historically used to justify colonialism and the unequal treatment of non-European peoples.
Furthermore, early anthropological research perpetuated stereotypes such as the inability to handle alcohol or being lazy, which are now recognized as false and prejudicial. Over time, anthropologists and historians have worked to dispel these misconceptions, revealing that non-Western societies were indeed complex, organized, and functional without adhering to Eurocentric standards of 'civilization.'