The corrido is a folk ballad of Mexico.
These popular narrative songs started to accrue political overtones during the Mexican War of Independence, but the high watermark of the corrido was the period surrounding the Mexican Revolution. A people’s history all of its own is contained in the many corridos of the Mexican Revolution, and before the widespread use of radio these songs were used to bring news to a largely illiterate population as well as to counteract the propaganda being spread by the Díaz government owned newspapers
The best known Revolutionary corrido is undoubtedly La Cucaracha (The Cockroach), an old song which, in its most famous form, was rephrased to celebrate the exploits of Pancho Villa’s army and send up his nemesis Venustiano Carranza.
A number of corridos, like the one Billy sings to the wolf, also celebrate the soldaderas, the women of the Mexican Revolution:
Maria Herrera-Sobek, The Mexican Corrido: A Feminist Analysis