Antedating of dining room
Casse-museau is a hard dry pastry still made today'...petits choux and gateaux feuilletes are mentioned in a charter by Robert, Bishop of Amiens in 1311." ---Larousse Gastronomique, completely revised and updated [Clarkson Potter: New York] 2001 (p. The original dividing line between cake and bread was fairly thin: Roman times eggs and butter were often added to basic bread dough to give a consistency we would recognize as cakelike, and this was frequently sweetened with honey.
Terminologically, too, the earliest English cakes were virtually bread, their main distinguishing characteristics being their shape--round and flat--and the fact that they were hard on both sides from being turned over during baking..England the shape and contents of cakes were graudally converging toward our present understanding of the term.
Whereas a cake may remain fresh for several days after baking or even improve with keeping, a gateau usually includes fresh decoration or ingredients that do not keep well, such as fresh fruit or whipped cream.
This is due to primarily to advances in technology (more reliable ovens, manufacture/availability of food molds) and ingredient availability (refined sugar). When removed the icing cooled quickly to form a hard, glossy [ice-like] covering.
At that time cake hoops--round molds for shaping cakes that were placed on flat baking trays--were popular. Many cakes made at this time still contained dried fruits (raisins, currants, citrons).
In its northeastern Old French dialect from wasel it as borrowed into English in the thirteenth century, where it survived until the seventeenth century." ---An A to Z of Food and Drink, John Ayto [Oxford University Press: Oxford] 2002 (p.
138) "The word 'gateau' crossed the Channel to England in the early 19th century...