|Dayton was born at Elizabethtown (present Elizabeth), NJ, in 1760. His father was a storekeeper who was also active in local and state politics. The youth obtained a good education, graduating from the College of New Jersey (later Princeton) in 1776. He immediately entered the Continental Army and saw extensive action. Achieving the rank of captain by the age of 19 and serving under his father, Gen. Elias Dayton, and the Marquis de Lafayette, he was a prisoner of the British for a time and participated in the Battle of Yorktown, VA.|
After the war, Dayton returned home, studied law, and established a practice. During the 1780s he divided his time between land speculation, legal practice, and politics. He sat in the assembly in 1786-87. In the latter year, he was chosen as a delegate to the Constitutional Convention after the leaders of his political faction, his father and his patron, Abraham Clark, declined to attend. Dayton did not arrive at Philadelphia until June 21 but thereafter faithfully took part in the proceedings. He spoke with moderate frequency during the debates and, though objecting to some provisions of the Constitution, signed it.
After sitting in the Continental Congress in 1788, Dayton became a foremost Federalist legislator in the new government. Although elected as a representative, he did not serve in the First Congress in 1789, preferring instead to become a member of the New Jersey council and speaker of the state assembly. In 1791, however, he entered the U.S. House of Representatives (1791-99), becoming Speaker in the Fourth and Fifth Congresses. During this period, he backed Hamilton's fiscal program, suppression of the Whisky Rebellion, Jay's Treaty, and a host of other Federalist measures.
In personal matters Dayton purchased Boxwood Hall in 1795 as his home in Elizabethtown and resided there until his death. He was elevated to the U.S. Senate (1799-1805). He supported the Louisiana Purchase (1803) and, in conformance with his Federalist views, opposed the repeal of the Judiciary Act of 1801.
In 1806 illness prevented Dayton from accompanying Aaron Burr's abortive expedition to the Southwest, where the latter apparently intended to conquer Spanish lands and create an empire. Subsequently indicted for treason, Dayton was not prosecuted but could not salvage his national political career. He remained popular in New Jersey, however, continuing to hold local offices and sitting in the assembly (1814-15).
In 1824 the 63-year-old Dayton played host to Lafayette during his triumphal tour of the United States, and his death at Elizabeth later that year may have been hastened by the exertion and excitement. He was laid to rest at St. John's Episcopal Church in his hometown. Because he owned 250,000 acres of Ohio land between the Big and Little Miami Rivers, the city of Dayton, was named after him--his major monument. He had married Susan Williamson, but the date of their wedding is unknown. They had two daughters.