One of the most important criteria for a certain quality and distinctiveness of a wine is the controlled geographical origin of the grapes from which it was pressed. The "controlled" means that the corresponding wine law specifications are also strictly checked on a regular basis. The most important reason is to protect against wine adulteration. Even in ancient times, there were isolated instances of the custom of naming wines according to their origin. Among the oldest European designations of origin are the area defined in 1716 for Chianti, and the boundaries defined in 1756 for Port. The great pioneer for a nationwide system, however, was France, where an appellation system (Appellation d'Origine Protégée) was adopted after the end of the First World War. This established a locally defined and controlled origin and production methods for agricultural products. Under the sovereignty of the INAO (Institut National des Appellations d'Origine), the rules for viticulture were perfected after the Second World War.
For me, Lexicon from wein.plus is the most comprehensive and best source of information about wine currently available.Egon Mark
Diplom-Sommelier, Weinakademiker und Weinberater, Volders (Österreich)