Manuel Rojas was born in Buenos Aires, Argentina, on January 8, 1896. His youth was spent between Argentina and Chile, influencing the settings of his stories like “The Glass of Milk.” He also traveled while working as an unskilled laborer. These experiences gave Rojas unique insight into the plights of the working or lower classes, which is reflected in his work.

As a young man, he became involved with various anarchist groups and contributed to anarchist journals. As in many parts of the world, the early 20th century saw a growing labor movement in Chile with workers forming unions and striking for better working conditions. Rojas wrote articles for anarchist newspapers based in Chile and Buenos Aires. La Batalla, the one in Buenos Aires, was one of the longer-running anarchist newspapers, publishing between 1912 and 1926. In 1933, the Socialist Party of Chile was founded, with the Popular Front Party taking control of the government in 1936. The Socialist Party helped ensure the survival of the left-wing coalition in Chile. In 1938, Rojas published a collection of essays titled De la Poesía a la Revolución. Anarchist ideas can be seen in “The Glass of Milk” in observations like calling the city “a place of slavery [where] people lived and died dazed by an anguished toil” (Paragraph 21).