Early settlers of the colony were ardent supporters of Oliver Cromwell and of democracy. Settlement preparations included sending a ship with an unusual cargo of ironwork for a portcullis and drawbridges, and even an experienced military engineer. Saybrook's fort was to be the strongest in New England. However, prominent Puritans soon "found the countrie [England] full of reports of their going", and they were worried that they would not be allowed to sell their estates and board their ship. By 1638, the plans for Saybrook were abandoned. The sponsors remained in England and played their respective political and military roles in the English Civil War and its aftermath. As a consequence, the colony struggled and, by 1644, the colony merged with the more vibrant Connecticut Colony a few miles up river.
In 1647, Major John Mason assumed command of Saybrook Fort, which controlled the main trade and supply route to the upper river valley. The fort mysteriously burned to the ground, but another improved fort was quickly built nearby. He spent the next 12 years there and served as Commissioner of the United Colonies, its chief military officer, Magistrate, and peacekeeper. He was continually called upon to fairly negotiate the purchase of Indian lands, write a treaty, or arbitrate some Indian quarrel, many of which were instigated by his friend Uncas.
Young, Alfred A. (1991). "English Plebeian Culture and 18th Century American Radicalism". In Jacob, Margret C.; Jacob, James R. (eds.). The Origins of Anglo American Radicalism. New Jersey: Humanities Press International. p. 195. ISBN978-1-57392-289-0. LCCN90023163.