candidate: Belgian journalist Jo Gérard claims that a 1781 family manuscript recounts that potatoes were deep - fried prior to 1680 in what was then the Spanish Netherlands ( present - day Belgium ) , in the Meuse valley : " The inhabitants of Namur , Andenne , and Dinant , had the custom of fishing in the Meuse for small fish and frying , especially among the poor , but when the river was frozen and fishing became hazardous , they cut potatoes in the form of small fish and put them in a fryer like those here .