[19] Millstone was incorporated as a borough by an act of the New Jersey Legislature on May 14, 1894, from portions of Hillsborough Township, based on the results of a referendum held that day.

[26] After the victory at Princeton on January 3, 1777, General George Washington headquartered at the Van Doren house, while the army camped nearby that night.

[32] The 2010 United States census counted 418 people, 162 households, and 118 families in the borough.

[39] As of the 2000 United States census[14] there were 410 people, 169 households, and 126 families residing in the borough.

The racial makeup of the borough was 97.56% White, 0.98% African American, 0.98% Asian, and 0.49% from two or more races.

[6] The borough form of government used by Millstone is a "weak mayor / strong council" government in which council members act as the legislative body with the mayor presiding at meetings and voting only in the event of a tie.

The mayor can veto ordinances subject to an override by a two-thirds majority vote of the council.

[41][42][43] As of 2022[update], the mayor of Millstone Borough is Democrat Raymond Heck, whose term of office ends December 31, 2022.

Members of the Millstone Borough Council are Council President Mandy Coppola (D, 2022), Robert Galli (I, 2024), Alan Kidd (R, 2023), Karin Kidd (2023), Kristen Ross (R, 2022) and Johnathan Stashek (D, 2024).

[3][44][45][46][47][48][49] In January 2019, the borough council selected Vincent Biviano from three candidates nominated by the Republican municipal committee to fill the seat expiring in December 2021 that had been won, but never filled, by Merry Emmich.

[50] Millstone is located in the 12th Congressional District[51] and is part of New Jersey's 16th state legislative district[52][53][54] Prior to the 2010 Census, Millstone had been part of the 4th Congressional District, a change made by the New Jersey Redistricting Commission that took effect in January 2013, based on the results of the November 2012 general elections.

[55] For the 119th United States Congress, New Jersey's 12th congressional district is represented by Bonnie Watson Coleman (D, Ewing Township).

[58] For the 2024-2025 session, the 16th legislative district of the New Jersey Legislature is represented in the New Jersey Senate by Andrew Zwicker (D, South Brunswick) and in the General Assembly by Mitchelle Drulis (D, East Amwell Township) and Roy Freiman (D, Hillsborough Township).

[59] Somerset County is governed by a five-member Board of County Commissioners, whose members are elected at-large to three-year terms of office on a staggered basis, with one or two seats coming up for election each year.

[76] Among the borough's 2010 Census population, 73.9% (vs. 60.4% in Somerset County) were registered to vote, including 96.9% of those ages 18 and over (vs. 80.4% countywide).

In 1814, a two-story building called the Academy was established as a co-ed public school on the lot owned by Daniel Disborough.

[88][87][89] Another classical school focusing on Latin started in 1826 at the home of Dominie Zabriskie.