During the dispute between Vermonters who held land titles from New Hampshire Governor Benning Wentworth and the government of New York, which tried to make them acquire titles from New York, Clark was a prominent anti-New Yorker, chairing meetings of citizens called to discuss the question and plan strategy and preparing written communications to New York's leaders.
In 1777 Clark served as a member of the committee that prepared the Declaration of Independence that created the Republic of Vermont, an entity which remained in existence until Vermont's acceptance into the Union as the 14th state in 1791.
Clark was active in the American Revolution, serving as chairman of Bennington's Committee of Satefy. In addition he served as a Commissary, helping supply the garrison at Fort Ticonderoga, and gathering and organizing the delivery of supplies to the army of Horatio Gates during the Saratoga Campaign. Several of Clark's sons saw military service, and one, Nathan Clark, Jr., was wounded at the Battle of Bennington and later died as a result. Another of Clark's sons, Isaac, served in the Revolution and the War of 1812. Isaac Clark married Hannah, one of the daughters of Governor Thomas Chittenden.
In 1778 Clark was elected to the first session of the Vermont House of Representatives. He was selected to serve as Speaker of the House after Joseph Bowker resigned in order to accept a seat on the Governor's Council.
Clark died in Bennington on April 8, 1792. He was buried in Bennington's Old Cemetery.
- Norwich Vital Records (1659-1848), published by Society of Colonial Wars in the State of Connecticut, 1913, Page 70
- List of Original Settlers of Vermont, the Bennington Museum, accessed March 7, 2012
- The History of Vermont, by Hiland Hall, 1868, page 459
- Vindication of Volume First of the Collections of the Vermont Historical Society, by Hiland Hall, 1871, page 16
- The Vermont Historical Gazetteer, by Abby Maria Hemenway, Volume 1, 1867, page 175
- Memorials of a Century, by Isaac Jennings, 1869, page 264
- Records of the Governor and Council of the State of Vermont, published by E. P. Walton (Montpelier), Volume 1, 1873, page 121
- Vermont State Papers, published by Vermont Secretary of State, 1823, pages 257 to 258
- Early History of Vermont, by Lafayette Wilbur, 1902, Volume 3, page 382
- History and Description of New England, by Austin Jacobs Coolidge and John Brainard Mansfield, 1860, page 745
- Gravestone photo by contributor "the moo", Find A Grave web site, accessed March 7, 2012
|Speaker of the Vermont House of Representatives
Thomas Chandler, Jr.