New York County Creation Dates and Parent Counties

Name of County	Date Formed	Parent County	Progeny County
Albany	01 Nov 1683	Colonial lands	Tryon 1772, Charlotte 1772, Greene 1800, Columbia 1786, Rensselaer 1791, Saratoga 1791, Schoharie 1795, Schenectady 1809
Allegany	07 Apr 1806	Genesee, Steuben (1808)	Genesee 1811, Wyoming 1846, Tioga 1822
Berkshire	28 May 1760	disputed area	in State of Massachusetts
Bronx	1914	New York, Westchester	none
Broome	28 Mar 1806	Tioga	Tioga 1822
Cattaraugus	11 Mar 1808	Genesee	none
Cayuga	08 Mar 1799	Onondaga	Seneca 1804, Tompkins 1817
Charlotte	12 Mar 1722	Albany	renamed Washington 1784
Chautauqua	11 Mar 1808	Genesee	none
Chemung	29 Mar 1836	Tioga	Schuyler 1854
Chenango	15 Mar 1798	Herkimer, Tioga	Oneida 1804, Madison 1806
Clinton	07 Mar 1788	Washington	St. Lawrence 1802, Oneida 1801, Essex 1799, Franklin 1808
Columbia	04 Apr 1786	Albany	none
Cortland	08 Apr 1808	Onondaga	none
Cumberland	1766	Albany	now in State of Vermont as one of originals
Delaware	10 Mar 1797	Ulster, Otsego	none
Dukes	01 Nov 1688	Colonial lands (dispute)	in State of Massachusetts
Dutchess	01 Nov 1683	Colonial lands	Albany 1717, Putnam 1812
Erie	02 Apr 1821	Niagara	Franklin 1808
Essex	01 Mar 1799	Clinton, Franklin	none
Franklin	11 Mar 1808	Clinton	Essex 1822
Fulton	18 Apr 1838	Montgomery	none
Genesee	30 Mar 1802	Ontario	Allegany 1806, Cattaraugus 1808, Chautauqua 1808, Niagara 1808, Livingston 1821, Monroe 1821, Orleans 1824, Wyoming 1841
Greene	30 Mar 1802	Ontario	see note
Hamilton	21 Feb 1816	Montgomery	none
Herkimer	16 Feb 1719	Montgomery, Otsego	Onondaga 1794, Oneida 1798, Chenango 1798
Jefferson	28 Mar 1805	Oneida	see note
Kings (Brooklyn)	01 Nov 1683	Colonial lands	none
Lewis	28 Mar 1805	Oneida, Jefferson	see note
Livingston	23 Feb 1821	Genesee, Ontario	see note
Madison	21 Mar 1806	Chenango, Oneida (1836)	none
Monroe	23 Feb 1821	Genesee, Ontario	none
Montgomery	12 Mar 1772	renamed from Tryon	Ontario 1789, Herkimer 1791, Otsego 1791, Tioga 1791, Hamilton 1816
Nassau	1899	Queens	none
New York (Manhattan)	1652	Colonial lands	none
Niagara	11 Mar 1818	Genesee	Erie 1821
Oneida	15 Mar 1798	Herkimer	Oswego 1816, Lewis 1805, Jefferson 1805, Clinton 1801, Madison 1836, Chenango 1804
Onondaga	05 Mar 1794	Herkimer	Oswego 1816, Cayuga 1799, Cortland 1808
Ontario	27 Jan 1789	Montgomery, Montgomery (1791), Steuben (1814)	Monroe 1821, Livingston 1821, Wayne 1823, Steuben 1796, Genesee 1802, Yates 1823
Orange	01 Nov 1683	Colonial lands, Ulster (1798)	Rockland 1798
Orleans	11 Nov 1824	Genesee, Genesee (1825)	none
Oswego	01 Mar 1816	Oneida, Onondaga	none
Otsego	16 Feb 1791	Montgomery	Schoharie 1795, Delaware 1797
Putnam	12 Jun 1812	Dutchess	none
Queens	01 Nov 1683	Colonial lands	Nassau 1899
Rensselaer	07 Feb 1791	Albany	none
Richmond (Staten Island)	01 Nov 1683	Colonial lands	none
Rockland	23 Feb 1798	Orange	none
St. Lawrence	03 Mar 1805	Clinton, Herkimer, Montgomery	none
Saratoga	07 Feb 1791	Albany	none
Schenectady	07 Mar 1809	Albany	none
Schoharie	06 Apr 1795	Albany, Otsego	Greene 1836
Schuyler	17 Apr 1854	Chemung, Steuben, Tompkins	none
Seneca	29 Mar 1804	Cayuga	Tompkins 1817, Wayne 1823
Steuben	18 Mar 1796	Ontario	Ontario 1814, Livingston 1822, Allegany 1808, yates 1824
Suffolk	01 Nov 1683	Colonial lands	none
Sullivan	27 Mar 1809	Ulster	none
Tioga	16 Feb 1791	Montgomery	Chenango 1798, Broome 1806, Chemung 1836, Tompkins 1822
Tompkins	17 Apr 1817	Cayuga, Seneca	Tioga 1822, Schuyler 1854
Tryon	12 Mar 1772	Albany	renamed Montgomery 1784
Ulster	01 Nov 1683	Colonial lands	Delaware 1797, Greene 1800, Orange 1798, Sullivan 1809
Warren	12 Mar 1813	Washington	none
Washington	02 Apr 1784	renamed from Charlotte	Clinton 1788
Wayne	11 Apr 1823	Ontario, Seneca	none
Westchester	01 Nov 1683	Colonial Lands	Bronx
Wyoming	14 May 1841	Genesee, Allegany (1846)	none
Yates	05 Feb 1823	Ontario	none