Okay, I am not an historian and I am also not a cook either (as my wife can attest) but when it comes to Newburyport, it is so important that historically unique foods be offered to Newburyport visitors. In fact, this uniquness should extend to many different products.
As for food, there are two that are well-established in this port city: Hardtack and Joe Froggers. Sailors and ships heavily depended on these two products to sustain them as they travelled the world. As a port city, our visitors aught to sample that importance and come away with an appreciation of our heritage.
I have downloaded the history for both complete with recipes and where to obtain them today in the "History" folder.