Samoireau and Cot are two different names for the same grape variety. Samoreau is a place name near Fontainebleau were François Ist had vines from Cahors (and elsewhere) planted in 1532-39. Under the name Samoireau, the variety was then spread towards Paris, Burgundy and the eastern Loire Valley vineyards: Orleans, Berry (Sancerre, Bourges). A synonym “plant du roi” (king’s vine) could explain the success of this variety in too far north regions for its regular ripening. In the western part of the Loire Valley (in the Sologne – Touraine- Anjou – Poitou vineyards), the variety was called Cors, Caux etc. This name, not attested earlier than the 18th cent., was very likely a contraction issued from the name of the town Cahors in Quercy where the variety is called Auxerrois (synonym Malbec in Bordeaux and elsewhere in the world). The use of Cors, Caux etc. ascertains a parallel way of circulation of the variety towards the Loire valley. The name Côt (Cot in the international nomenclature) itself was chosen among others by ampelographs around 1800 and popular by 1850. The use of the name Samoireau had almost disappeared by the mid 19th cent.