The Yanaconas (Yanakuna) were a hereditary class of Indigenous servants in South America. Early in the history of Spanish conquest, the King granted to his favorites an "encomienda," or rights to use a piece of land, recruit Indigenous labor, and collect taxes, as long as the encomendero resided on the land. Over time the rights were limited by the government, including the amount of tax collected from them, and the fact that the Yanaconas could not be taken and sold as slaves, but must remain as part of the specific piece of land.

Mizque, spelled Misque in the document, is now located in Bolivia; in 1734, however, it was part of the Viceroyalty of Peru, which included much of South America. It was divided into subordinate areas, presidencies, each with its own governor, and administrative and judicial tribunal, or audiencia. The Viceroy was the Governor of the central presidency, and also the presidency of Charcos in which Mizque was located.

The collection comprises an official handwritten copy, dated the 6th of January, 1754, of a petition by the procurador general of the town council of Mizque to the Viceroy of Peru, on behalf of the Yanaconas Indians. It protests the practice of the corregidor, the chief magistrate of the province, of charging an annual tax of seven pesos per head rather than the three pesos and one real stipulated by the Viceroy. A memorial by the Jesuit Pedro Foronda, member of the Spanish Parliament, expresses views on the subject. The Viceroy's decision in favor of the Yanaconas is given. All written in one clear hand, then signed by General Iñigo Abendano, Chief Magistrate and Chief Justice of Potosí, with a countersignature by Manuel Santos de Therrazas.