The literary movement of Indigenism of the early 20th century reflects the heterogeneity of the people inhabiting the countries of the Andes and tries to appropriately express their cultural identity in works of literature. For the first time the indigenous authors wanted to give voice to the views of the suppressed indigenous population in literature by depicting the indios as authentically as possible. The authors whose works are being analysed in this study, Jorge Icaza, Ciro Alegría and José María Arguedas, mainly represent their linguistic and cultural heterogeneity by using and blending the Indian language Quechua and Spanish. In the analysis of the works the theme of multilingual literature plays a central role when it comes to the representation of heterogeneity. The way Quechua is used in Spanish texts sheds light on the linguistic and cultural diversity between indios, mestizos and the white population who live together in the Andes and influence each other. Each of the authors has a personal approach to this phenomenon and represents it in his works in varying ways, due to different intentions and experiences with the world of Quechua.As Quechua can be found in the narrative text as well as in the character speech, both are being analysed separately. In order to examine the heterogeneity represented in the texts, the question has to be raised why the authors use Quechua in different cases and what functions and effects the insertion of a foreign language has in a work of literature. Given that this multilingual approach mostly affects the reader?s comprehension of the text, the works? orientation towards the recipient and their reasonability for a reader who does not speak Quechua are part of the analysis. It is the aim of this study to come to an overall picture of the linguistic and cultural heterogeneity represented in the selected works by an accurate linguistic and literary analysis.