The link below will take you to an article that shows how ancient peoples fermented grains long before they were domesticated.  Apparently, early brewers collected grain from as far away as sixty miles to provide for their buzz. This search for beer caused the domestication of grains so that beer could be produced more easily and in larger quantities. They learned that by planting grains, they only need 1% of the land and couId sell the surplus. This lead to villages then cities, and the rest is history.
I found this article to be very interesting, but I am still wondering about that first fellow who brewed the first pilsner, or was it lager? Read on for the details and see the evidence. 
http://www.google.com/gwt/n?u=http://www.science20.com/timberati/civilization_and_beer_an_enormous_improvement_on_the_lack_thereof-137846