This article aims to examine the ways in which King John VI and his ruling were represented in the XIX century Portuguese historiography, drawing on a representative corpus of historical sources. First as Prince Regent and after his mother's death, D. Maria I in 1816, as acclaimed King, John (1767-1826) reigned during a most crucial period in the nation's history. His ruling corresponded to an eventful and arduous transition period from the Old Regime to the modern era, shaped by the impact of the French invasions, the exile of the royal family and the Portuguese court to Brazil, the first liberal revolution, the independence of the Brazilian colony and by deep political tensions amongst the ruling elite and the royal family itself. In an especially difficult and controversial period, Prince John, whose character was perceived as not being particularly suited for the throne, became the heir after his older brother's death. Furthermore, due to the mental illness of his mother he was forced to assume the reins of government when he was only 24 years of age. Known as John, the Clement, he, however, met a treacherous death with high suspicions of have been poisoned. At a personal level as well as a reigning sovereign he had to face a life of hardships. Thus, it is important to explore the nature of nineteenth century historians' accounts and the ways they have represented him for posterity.