In the nineteenth century, realism had been the technique of the bourgeois novelist who wished to show with as much verisimilitude and objectivity as possible the relationship between the individual and his society. In the '30s realism took on a new meaning. Its purpose was to show not only the workings of society but in particular economic exploitation, the class-struggle and the new forces among working class and peasantry who were to change the situation. This type of realism was known as socialist realism. However, even among writers who were not Communists, the prevailing mood of economic depression encouraged a concentration on those sectors of society which seemed actually or potentially the most militant. In Europe these were the years of the ‘proletarian’ novel whose heroes were miners and factory workers. In Latin America, where the proletariat was almost nonexistent, some writers found their Latin-American equivalent in the small industrial enclaves such as oil and mine fields, amongst the dockers or the city Lumpenproletariat: more often, the writer found his material among the peasants and agricultural workers or the Indians.

Novels about Indians, agricultural workers or even poor citydwellers were not exactly new in Spanish–American literature. Clorindo Matto de Turner, Heriberto Frías and Alcides Arguedas had already registered their protest at the treatment of the Indians; the criollista writers had covered almost every area of peasant life.