PRINCETON, a borough and township of the United States, in Mercer county, New Jersey, on the Delaware and Rariton Canal, 3 miles north by rail from Princeton Junction, which is 48 miles south-west of New York and 42 north-east of Philadelphia on the Pennsylvania Railway. Standing on high ground, it commands a fine prospect towards the east and south. The town is the seat of Princeton or New Jersey College, founded in 1746 by members of the presbytery of New York, chartered in the same year, and opened at Elizabethtown (now Elizabeth) in 1747, removed to Newark in the same year and rechartered in 1748, and finally transferred in 1756 to Princeton, where Nassau Hall, so called in honour of William III. of England, had been erected. Nassau Hall has been twice burned down, in 1802 and 1855, but was restored in 1856 in the old style. This building, Reunion Hall (1870), West College (1836), East College (1833), and the halls of the American Whig and Cliosophic literary societies enclose a quadrangle; and eastward, in the line of Nassau Hall or the north front, stand the library buildings (1873), consisting of an octagonal centre with two rings, the Dickinson Hall (1870), and the John C. Green School of Science (1873). Along the western border of the grounds are University Hall (1876), the Halstead observatory (1867), the gymnasium (1869), Witherspoon Hall (1876), and Edwards Hall (1879), while on the east are the Marquand Chapel (1881), Murray Hall (1877), and the residence of the president. Almost all these buildings are the gifts of generous benefactors, the most munificent of whom was Mr John C. Green, by whom and by the trustees of his estate not less than $1,500,000 has been given in buildings and endowments. In 1884 the college, which is steadily growing, had 39 professors and 519 students, and the library contained 77,000 volumes. The endowments amount to $1,392,000. The governor of the State of New Jersey is ex officio president of the board of trustees, who are twenty-five in number besides the president of the college. The trustees appoint the members of the faculty and have entire control over the funds and property of the college. They fill all vacancies in their own body. Besides the Halstead observatory, there is another well-equipped observatory at the School of Science, and the laboratories and museum are well furnished for scientific study. In the cemetery, which lies to the north of the college, are the tombs of Jonathan Edwards, Aaron Burr, &c. Princeton is also the seat of the oldest theological seminary of the Presbyterian Church in the United States (founded in 1812), with 7 professors, 1 instructor, about 150 students, and an endowment of about a million dollars. The population of the township in 1870 was 3986 and of the borough 2798, and in 1880 respectively 4348 and 3209. (See also Universities.)

At Princeton on 3d January 1777 Washington defeated the British forces; the Continental Congress met in the town (Nassau Hall) from 26th June to 4th November 1783.