Zephaniah Platt (May 27, 1735 – September 12, 1807) was an American politician and lawyer, and founder of the U.S. town of Plattsburgh, New York.
Platt was born in Huntington, New York, and received an English education. He was a direct descendant of Richard Platt (1603–1684), who was born in Ware, Hertfordshire, England, and settled in the Connecticut Colony.
==Legal and political career==
Zephaniah Platt practiced law in Poughkeepsie, New York, and was a member of the New York Provincial Congress (1775–1777), Committee of Safety (1777), State Senate (1777–1783), Congress of the Confederation (1785 and 1786), Council of Appointment (1778 and 1781). He was a Dutchess County judge from 1781 to 1795 and delegate to the New York Constitutional Convention in 1788.
==Founding of Plattsburgh==
He founded the town of Plattsburgh, New York, in 1788 and moved there in 1798 to continue practicing law. He was an originator of the Erie Canal, and was a regent of the State University of New York from 1791 until his death, in Plattsburgh, in 1807.
Platt was married twice, first to Mary Hannah Davis in 1756 and had two children:
* Zephaniah Platt 1756–1830
* Hannah (Comstock) Platt (born March 26, 1758)
In 1761 he married Mary Van Wyck Platt (1742–1809) and had 12 children including:
* Jonas Platt (1769–1834) was a U.S. Representative for the 9th Congressional District of New York (1799–1801), lawyer and associate justice of the New York State Supreme Court
* Charles Z. Platt (1773–1822) was a New York State Assemblyman for Oneida County (1807–1813) and New York State Treasurer (1813–1817)
Platt’s grandson (son of Jonas Platt) Zephaniah Platt was Michigan Attorney General.