The course is extremely rich in history; founded in 1898, the course was originally a four-hole layout. Over the next 18 years, the course was enlarged to a six, nine, eleven, and eventually eighteen-hole track. Then, in 1916, famed golf course architect Donald Ross redesigned the course layout (one of only five courses in the State of Connecticut that he designed), and in 1919, he rerouted three of the holes to complete his work. The course remained this way until 1997, in which a land swap with Pfizer gave the course the property to build three holes overlooking the water.
Over the years, many famous golfers have walked the fairways at Shennecossett, including Arnold Palmer, Walter Hagen, Bobby Jones, Tommy Armour, Francis Ouimet, Babe Didrikson, Marion Hollins, Glenna Collett, and former club professionals Alex Smith and Harry Cooper.
Since April 10, 1969, due to the purchase of the course by the Town of Groton, Shennecossett has been open to the residents of Groton and surrounding communities for public play (the only public Donald Ross designed course in the state).
Shennecossett continues to host premier Connecticut golf events, such as the Connecticut Senior Open, and furthers its reputation as one of the best public golf courses in the state. In September of 2007 Shennecossett was featured in Golf Magazine as one of the "Thrifty Fifty" (view article) in the United States; best public access courses that one can play for under $50. Shennecossett was featured in The Best of Northeast Golf 2007 Reader's Choices as one of the best overall conditioned courses and best overall courses.