John Holbrook was born August 12, 1726, the only son of John and Abigail (Gunn) Holbrook. As a man he lived on Great Hill in a house which his father built between 1740 and 1745.
    His title of captain came from his rank in the local militia of Derby.
    He was married first to Esther Nichols, daughter of Nathaniel and Ann (Booth) Nichols of Newtown. His second marriage was to Abigail Beers, widow of Noah Tomlinson. With his two successive wives, he had a total of fourteen children. Of these, only eight survived childhood and became adults.
    As early as 1774, the old Town of Derby was supporting the cause of the American Revolution. On November 29, of that year, a special town meeting was held to consider the "doings of the Reputable Continental Congress held at Philadelphia, September 5th 1774." The townspeople agreed that the proposal put forward by Congress was a wise and judicious plan." A special committee was appointed to take action on the proposal. Captain John Holbrook was a member of this committee. It was further provided that if a county Congress should be agreed upon in New Haven County, then the committee would appoint two members of the committee to attend the Congress. A county Congress was never called, and no further action was taken.
    In 1775, a special "Committee of Inspection" was formed at a special town meeting held on December 11th. This committee was appointed seven months prior to the Declaration of Independence. The committee was to watch the activities of suspected Tories or Loyalists and limit their travel throughout the area, so as to prevent their giving aid to the King's troops. John Holbrook was appointed to this committee which he served throughout the war.
    With the outbreak of Revolutionary hostilities, Holbrook became dissatisfied with the Derby Anglican (Episcopal) Church which was then under the leadership of the Rev. Richard Mansfield - Holbrook was opposed to Mansfield's preaching of submission to the King. This caused him to break from the church which his father had founded. Holbrook joined the Congregational Church in Derby and kept his membership there until 1779.
    The Rev. Mansfield attributed his departure from the