History When was each U.S. county first colonized

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I want to check this for each county within the contiguous United States.
Then I will make maps or a YT video showing how settlement expanded.

Let's start with Alabama:

County Year first colonized Oldest settlement
Mobile 1702 Mobile
Sumter 1736 Tombecbe
Baldwin 1784 Tensaw
Clarke 1789 Choctaw Bluff
Washington 1789 St. Stephens
Madison 1805 Huntsville
Colbert 1810 Leighton
Jefferson 1813 Jonesboro
Henry 1814 Franklin
Bibb 1815 Centreville
Butler 1815 Pine Flat
Conecuh 1815 Bellville
Elmore 1815 Wetumpka
Franklin 1815 Russellville
Lowndes 1815 Lowndesboro
Monroe 1815 Claiborne
Shelby 1815 Montevallo
Walker 1815 Jasper
Barbour 1816 Eufaula
Blount 1816 Blountsville
Covington 1816 Green Bay
Crenshaw 1816 Honoraville
Escambia 1816 Green's Bluff
Hale 1816 Greensboro
Lamar 1816 Bankhead
Tuscaloosa 1816 Tuscaloosa
Autauga 1817 Washington
Greene 1817 Hopkins Settlement
Marengo 1817 Demopolis
Morgan 1817 Somerville
Perry 1817 Marion
Pickens 1817 Pickensville
St. Clair 1817 Ashville
Lauderdale 1818 Florence
Lawrence 1818 Courtland
Limestone 1818 Mooresville
Montgomery 1818 Alabama Town
Chilton 1819 Old Maplesville
Dallas 1819 Cahaba
Geneva 1819 Geneva
Jackson 1819 Sauta
Wilcox 1819 Prairie Bluff
Houston 1820 Columbia
Winston 1820 Houston (now Lynn)
Fayette 1821 LaFayette
Marion 1821 Pikeville
Pike 1821 China Grove
Etowah 1825 Double Springs
Dale 1827 Daleville
Russell 1830 Glennville Beat
Bullock 1832 Midway
Clay 1832 Lineville
Coosa 1832 Rockford
Cullman 1832 Simcoe
Tallapoosa 1832 Suzanna
Calhoun 1833 Jacksonville
Chambers 1833 LaFayette
Macon 1833 Tuskegee
Randolph 1833 Louina
Choctaw 1833 Barrytown
Talladega 1834 Talladega
Cleburne 1835 Edwardsville
Lee 1835 Salem
Cherokee 1836 Cedar Bluff
Coffee 1836 Bridgeville
Marshall 1836 Claysville
DeKalb 1837 Lebanon

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Arizona:

County Year first colonized Oldest settlement
Santa Cruz 1752 Tubac
Cochise 1776 Santa Cruz de Terrenate
Pima 1776 Tucson
Apache 1851 Fort Defiance
Yuma 1852 Yuma
La Paz 1862 La Paz
Maricopa 1863 Wickenburg
Mohave 1863 Mohave City
Yavapai 1864 Prescott
Pinal 1866 Florence
Coconino 1872 Tuba City
Graham 1873 Munsonville
Greenlee 1873 Clifton
Gila 1875 Globe
Navajo 1876 Joseph City

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However, it can be noted that in two counties of Arizona Native Americans are still majority/plurality of population:

Apache County
Navajo County

 

[Tomenable]

Arkansas:

(in this case it is more of a patchwork, without a clear east-to-west or west-to-east pattern like in case of Alabama)
(also - interestingly - Arkansas was settled not much later than Alabama, despite being located further to the west)

County Year first colonized Oldest settlement
Arkansas 1686 Arkansas Post
White 1789 Georgetown
Crittenden 1795 Hopefield
Monroe 1799 Clarendon
Pulaski 1807 Crystal Hill
Hempstead 1808 Columbus
Lafayette 1808 Columbus
Garland 1809 Hot Springs
Desha 1810 Napoleon
Izard 1810 Lafferty Creek
Prairie 1810 Des Arc
Clark 1811 Arkadelphia
Boone 1812 Lead Hill
Independence 1812 Batesville
Montgomery 1812 Caddo Gap
Hot Spring 1815 Rockport
Phillips 1815 Helena
Randolph 1815 Pocahontas
Clay 1816 Peach Orchard
Lawrence 1816 Powhatan
Miller 1816 Lost Prairie
Saline 1817 Saline Crossing
Sebastian 1817 Fort Smith
Conway 1818 Cadron
Crawford 1818 Van Buren
Faulkner 1818 Cadron
Howard 1818 Center Point
Jefferson 1819 Pine Bluff
Ouachita 1819 Camden
Greene 1821 Crowley's Settlement
Lonoke 1821 Moss Prairie
Chicot 1822 Villemont
Woodruff 1822 Augusta
Yell 1823 Dardanelle
Cleveland 1824 Pennington Township
Poinsett 1824 Bay Village
Baxter 1825 Norfork
Bradley 1825 Warren
Polk 1825 Dallas
Scott 1825 Boles
Sharp 1825 Ash Flat
Lincoln 1827 Auburn
Madison 1827 Huntsville
St. Francis 1827 Franklin
Washington 1827 Cane Hill
Benton 1828 Maysville
Logan 1828 Booneville
Sevier 1828 Paraclifta
Johnson 1829 Spadra
Pope 1829 Norristown
Union 1829 Champagnolle
Perry 1830 Old Perryville
Pike 1830 Antoine
Stone 1830 Sylamore
Mississippi 1831 Osceola
Jackson 1832 Litchfield
Marion 1832 Yellville
Carroll 1833 Carrollton
Van Buren 1833 Bloomington
Craighead 1835 Greensboro
Searcy 1835 Bear Creek
Franklin 1836 Ozark
Little River 1836 Laynesport
Columbia 1837 Atlanta
Drew 1837 Rough and Ready
Nevada 1837 Moscow
Lee 1838 Walnut Bend
Fulton 1839 Salem
Grant 1839 Old Belfast
Cleburne 1840 Quitman
Newton 1840 Jasper
Calhoun 1841 Chambersville
Ashley 1842 Fountain Hill
Dallas 1842 Tulip
Cross 1845 Wittsburg

Spoiler

BTW if you think that you found an error in my list, please report it, and I will re-evaluate my data.

 

[Tomenable]

But if we look at numbers of settlers, then Arkansas was truly colonized later than Alabama:
(which indicates that most of the early settlements in Arkansas were very small settlements)

Alabama:

Year when settler population exceeded 5,000 - 1805
Year when settler population exceeded 50,000 - 1814
Year when settler population exceeded 100,000 - 1817

Arkansas:

Year when settler population exceeded 5,000 - 1813
Year when settler population exceeded 50,000 - 1833
Year when settler population exceeded 100,000 - 1841

Arizona:

Year when settler population exceeded 5,000 - 1864
Year when settler population exceeded 50,000 - 1887
Year when settler population exceeded 100,000 - 1901