United States State and Territory Formation Years
1776	1777	1783	1784	1785	1786	1787	1790	1791	1792	1795	1796	1798	1800	1802
1803	1804	1805	1809	1810	1812	1816	1817	1818	1819	1820	1821	1822	1824	1828
1834	1836	1837	1838	1842	1845	1846	1848	1849	1850	1853	1854	1858	1859	1860
1861	1862	1863	1864	1866	1867	1868	1870	1876	1882	1889	1890	1893	1896	1907
1912
U.S. County Formation Maps inbetween Census Years:
1790-1799		1800-1809		1810-1819		1820-1829		1830-1839		1840-1849		1850-1859
1860-1869		1870-1879		1880-1889		1890-1899		1900-1909		1910-1920
U.S. County Formation Maps all Years:
1643-Present			1643-1699		1700-1799		1800-1899		1900-Present