Since grains have been a staple food for millennia, the activity of baking is a very old one. Control of yeast, however, is relatively recent. By the fifth and sixth centuries BCE, the ancient Greeks used enclosed ovens heated by wood fires; communities usually baked bread in a large communal oven.
Greeks baked dozens and possibly hundreds of types of bread; Athenaeus described seventy-two varieties. In ancient Rome several centuries later, the first mass production of breads occurred, and "the baking profession can be said to have started at that time. Ancient Roman bakers used honey and oil in their products, creating pastries rather than breads.
In ancient Rome, bakers (Latin, pistor) were sometimes slaves, who were (like other slave-artisans) sometimes manumitted. Large households in Rome normally had their own bakers. The Gauls are credited with discovering that the addition of beer froth to bread dough made well-leavened bread, marking the use of controlled yeast for bread dough.
In medieval Europe, baking ovens were often separated from other buildings (and sometimes located outside city walls) to mitigate the risk of fire. Because bread was an important staple food, bakers' production factors (such as bolting yields, ingredients, and loaf sizes) were heavily regulated.