Old Keg Root Beer traces its origins to Reading, Pennsylvania, where it was introduced by the Excelsior Bottling Company in the early 1940s. While the Old Keg name first appears in surviving records in 1941, the company behind it had already built a reputation that stretched back nearly fifty years. Excelsior Bottling Company was founded in the 1890s by Thomas J. Fessler and S. G. Dunkelberger, experienced bottlers who helped establish the company as one of Reading's respected beverage producers. From its Maple Street bottling works, Excelsior manufactured ginger ale, seltzer, and other carbonated soft drinks while also bottling traditional malt beverages. By the time Old Keg was introduced, the company had survived changing tastes, Prohibition, and the challenges of an evolving beverage industry.

Old Keg reflected that rich heritage. Rather than following the trend toward brightly marketed novelty sodas, it embraced the image of an old-fashioned root beer with a smooth, full-bodied character. Its original slogan, "Real Draught Taste," captured the company's goal of creating a root beer reminiscent of the rich flavor associated with beverages drawn fresh from the keg. Like many regional soft drinks of its era, Old Keg was produced by an independent bottler serving its local community at a time when hundreds of family-owned bottling companies gave America an incredible variety of hometown flavors. Although much of Old Keg's early story has been lost to time, it remains an excellent example of the craftsmanship and pride that defined regional bottling during the golden age of American soft drinks.

Today, Old Keg stands as a tribute to those independent bottlers whose creativity and dedication helped shape America's rich soda heritage. Sweetened with real cane sugar and inspired by the traditions of the original brand, it offers today's root beer enthusiasts a taste of one of Pennsylvania's classic regional favorites.