The founding of the Franciscan Convent in Mesão Frio does not have a precise date. Fortunato de Almeida, the renowned author of "History of the Church of Portugal" stated, "The Monastery of St. Francis of Mesão Frio was founded in 1724, for monks." Conversely, Henry Frei Rema posited the year 1744 as the probable date of its founding. A third possible theory is that the construction of a house for the Franciscan friars at Mesão Frio began in 1724, and was not completed until twenty years later.

One certainty regarding the Franciscan Convent at Mesão Frio is that its history and secrets are shrouded in local legends. Since 1834, the building has served as the location of various public judiciary, administrative, and municipal offices for the village of Mesão Frio.