Quote Originally Posted by Gillman
light (helles) Munchener must have come in later.
Yes, until the science of the manipulation of minerals in water was understood in the early 20th century, beer styles were determined by the water of an area. Munich water, and that of much of Bavaria, has water that is high in alkalinity (like Kentucky water), which needed the acidity of dark malts to mash properly.

Kentucky bourbon is, of course, all pale malt (plus corn and rye or wheat). To balance the alkalinity of its limestone water and produce the proper mash pH, sour mash is used.