The D.L. Geary Brewing Company was incorporated in October, 1983 by David and Karen Geary who shared the vision of producing world class products on a small scale for local and regional consumption. At that time, there were only 13 so-called microbreweries in the United States, almost all of them in California and the Pacific Northwest. In the winter of 1984, David Geary began a period of training and research in Scotland and England. With the help of Peter Maxwell Stuart, a Scottish nobleman and brewer who arranged introductions and itineraries, he worked in a half-dozen small commercial breweries from the highlands of Scotland to the south coast of England.

During that time, the size and design of the brewery began to take shape; and most importantly, the recipe for Geary's Pale Ale was created using classic elements from some of Britain's best breweries. In the summer of 1984, Karen and David Geary began the long and difficult process of creating a business plan, finding appropriate real estate, specifying equipment and raw materials, designing packaging and raising the capital necessary to begin brewing. After nearly two years of planning and effort, construction began. Equipment was ordered, contractors were hired, and the brewery was ready for its first brewing the fall of 1986. On December 10, 1986, the first pints of Geary's Pale Ale were sold; New England's first microbrewery had arrived.

Since then, Geary's has increased its product line to seven full time products and three seasonal specialties, all in various package sizes, and has spread distribution to fifteen states along the eastern seaboard and as far west as Ohio. David and Karen still work at the facility as does their daughter, Kelly Geary Lucas.