Voltaire’s Siècle de Louis XIV (1751) is considered one of the most representative outcomes of Enlightenment historical inquiry, characterised by a new focus on the arts and sciences – as opposed to a more traditional focus on genealogy and warfare. Nevertheless, Voltaire accorded much prominence to court politics in his historical narrative, having acquired information from former politicians, such as Louis XIV’s minister Colbert de Torcy. This article introduces the reader to an unpublished manuscript, containing the copy of an otherwise lost text of Voltaire, and some original notes of Torcy on Francesco Ottieri’s history of the Spanish succession. It argues that the Siècle’s author considered the retired ‘man of action’ an authoritative source for the history of recent events – even when the latter had been a major political actor in these events. Voltaire’s view in this respect, together with his practice of not citing his sources, was not shared by some contemporary critics, negatively affecting their assessment of his historical work.