In 1787, long after the American Revolution had ended, Holbrook was still a community leader. The American states were then considering changes or replacement of the Articles of Confederation, which was the basis of early federal government. A new constitution was proposed by the Congress.
    Derby townspeople met and voted their support of the proposed change in government with the following resolution:
    "Resolved that this town will instruct, and that it hereby does instruct its representatives in the General Assembly to use their influence to have a Convention called as speedily as possible for the purpose of taking into consideration the Constitution proposed by the Federal Convention, agreeable to the recommendation of Congress; in hopes that the business may be entered upon at an early period by the legislature." The resolution was passed unanimously. Captain John Holbrook and Captain Daniel Holbrook were appointed delegates to the State Convention.
    In May, 1779, Holbrook and others applied to the Connecticut General Assembly to form a Great Hill Congregational Church. At that time, the formation of the established churches was by state legislation. The legislation was granted, and the Congregational Church at Great Hill was founded.
    Holbrook, at this time, was quite wealthy, owning a thousand acres of land, a saw mill, and much personal property. He contributed the use of his saw mill and timber for the construction of the Great Hill meeting house.
    Mary Louise Holbrook, in her book The Holbrook Family of Derby, Connecticut, wrote as follows:
    "Captain John was one of the town's most reliable and trustworthy men, with much firmness of purpose and a strict integrity. His judgment was reliable and the younger members of the family sought, prized and relied upon his counsels. He was liberal in his charities but firm and unchangeable for the right as an anecdote will illustrate." When building the Church . . . he gave the committee liberty to cut any timber excepting three trees, which they were strictly forbidden to touch. On looking around they found those trees to be just what they wanted and took them expecting to effect a reconciliation with him. They appointed