Alcona County	001	Harrisville	1840 (boundaries declared)
1869 (organized)	From unorganized territory; named Negwegon County until 1843	Schoolcraft pseudo-Native American name	10,942	1,791 sq mi
(4,639 km2)	State map highlighting Alcona County
Alger County	003	Munising	1885	From part of Schoolcraft County	Russell A. Alger, (1836-1907):
Governor and national politician	9,601	5,049 sq mi
(13,077 km2)	State map highlighting Alger County
Allegan County	005	Allegan	1831 (boundaries declared)
1835 (organized)	From part of Barry County, and unorganized territory	Pseudo-Schoolcraft pseudo-Native American name	111,408	1,833 sq mi
(4,747 km2)	State map highlighting Allegan County
Alpena County	007	Alpena	1840 (boundaries declared)
1857 (organized)	From part of Mackinac County, and unorganized territory Was named Anamickee County until 1843.	Schoolcraft pseudo-Native American name	29,598	1,695 sq mi
(4,390 km2)	State map highlighting Alpena County
Antrim County	009	Bellaire	1840	From part of Mackinac County; named Meegisee County until 1843	County Antrim, Ireland	23,598	602 sq mi
(1,559 km2)	State map highlighting Antrim County
Arenac County	011	Standish	1831	From unorganized territory; annexed to Bay County in 1857, but reinstated in 1883	Schoolcraft pseudo-Native American name	15,899	681 sq mi
(1,764 km2)	State map highlighting Arenac County
Baraga County	013	L'Anse	1875	From part of Houghton County	Frederic Baraga (1797-1868): Catholic missionary and first bishop of Sault Ste. Marie	8,860	1,069 sq mi
(2,769 km2)	State map highlighting Baraga County
Barry County	015	Hastings	1829	From unorganized territory	William T. Barry (1784-1835): Postmaster General in the Jackson Administration	59,173	577 sq mi
(1,494 km2)	State map highlighting Barry County
Bay County	017	Bay City	1857	From parts of Arenac, Midland, and Saginaw Counties	Saginaw Bay	107,771	631 sq mi
(1,634 km2)	State map highlighting Bay County
Benzie County	019	Beulah	1863	From part of Leelenau County	French name of Betsie River: (riviè aux) Bec-scies, the "(river of) sawbill ducks"	17,525	860 sq mi
(2,227 km2)	State map highlighting Benzie County
Berrien County	021	St. Joseph	1829	From unorganized territory	John M. Berrien (1781-1856): Attorney General in the Jackson Administration	156,813	1,581 sq mi
(4,095 km2)	State map highlighting Berrien County
Branch County	023	Coldwater	1829	From unorganized territory	John Branch (1782-1863): Secretary of the Navy in the Jackson Administration	45,248	519 sq mi
(1,344 km2)	State map highlighting Branch County
Calhoun County	025	Marshall	1829	From unorganized territory	John C. Calhoun (1782-1850): Vice President of the United States in the Jackson Administration	136,146	718 sq mi
(1,860 km2)	State map highlighting Calhoun County
Cass County	027	Cassopolis	1829	From unorganized territory	Lewis Cass (1782-1866): Secretary of War in the Jackson Administration	52,293	508 sq mi
(1,316 km2)	State map highlighting Cass County
Charlevoix County	029	Charlevoix	1869	From parts of Antrim, Emmet, and Otsego Counties	Pierre Françs Xavier de Charlevoix (1682-1761): Jesuit traveller and historian of New France	25,949	1,391 sq mi
(3,603 km2)	State map highlighting Charlevoix County
Cheboygan County	031	Cheboygan	1840	From part of Mackinac County	Cheboygan River	26,152	885 sq mi
(2,292 km2)	State map highlighting Cheboygan County
Chippewa County	033	Sault Ste. Marie	1827	From part of Mackinac County	Ojibwa Native American tribe, also known as the Chippewa	38,520	2,698 sq mi
(6,988 km2)	State map highlighting Chippewa County
Clare County	035	Harrison	1840	From part of Mackinac County, and unorganized territory; named Kaykakee County until 1843	County Clare, Ireland	30,926	575 sq mi
(1,489 km2)	State map highlighting Clare County
Clinton County	037	St. Johns	1831	From unorganized territory	DeWitt Clinton (1769-1828): Governor of New York.	75,382	575 sq mi
(1,489 km2)	State map highlighting Clinton County
Crawford County	039	Grayling	1840	From part of Mackinac County and unorganized territory. Was named Shawano County until 1843.	William Crawford, (1732-82), American Revolutionary War colonel western surveyor	14,074	563 sq mi
(1,458 km2)	State map highlighting Crawford County
Delta County	041	Escanaba	1843	From part of Mackinac County and unorganized territory.	Greek letter delta, referring to the triangular shape of the original county, which included segments of Menominee, Dickinson, Iron and Marquette counties	37,069	1,992 sq mi
(5,159 km2)	State map highlighting Delta County
Dickinson County	043	Iron Mountain	1891	From parts of Iron County, Marquette County and Menominee County.	Donald M. Dickinson (1846-1917): Postmaster General in the Cleveland Administration	26,168	777 sq mi
(2,012 km2)	State map highlighting Dickinson County
Eaton County	045	Charlotte	1829	From unorganized territory.	John Eaton (1790-1856): Secretary of War in the Jackson Administration	107,759	579 sq mi
(1,500 km2)	State map highlighting Eaton County
Emmet County	047	Petoskey	1840	From part of Mackinac County. Was named Tonegadana County until 1843.	Robert Emmet (1778-1803): Irish nationalist and rebel leader	32,694	882 sq mi
(2,284 km2)	State map highlighting Emmet County
Genesee County	049	Flint	1835	From parts of Lapeer County, Saginaw County and Shiawassee County.	Seneca word, "je-nis-hi-yeh," meaning "beautiful valley": named after western New York valley from which many settlers came	425,790	649 sq mi
(1,681 km2)	State map highlighting Genesee County
Gladwin County	051	Gladwin	1831	From unorganized territory.	Major Henry Gladwin, British commander of the fort at Detroit during the siege by Chief Pontiac in 1763-64.	25,692	516 sq mi
(1,336 km2)	State map highlighting Gladwin County
Gogebic County	053	Bessemer	1887	From part of Ontonagon County.	Probably from the Chippewa "bic" which most references interpret as "rock."	16,427	1,476 sq mi
(3,823 km2)	State map highlighting Gogebic County
Grand Traverse County	055	Traverse City	1851	From part of Omeena County.	French grande traverse[note 1] ("long crossing"), given first to Grand Traverse Bay by French voyageurs.	86,986	601 sq mi
(1,557 km2)	State map highlighting Grand Traverse County
Gratiot County	057	Ithaca	1831	From unorganized territory.	Captain Charles Gratiot (1788-1855), built Fort Gratiot at the present site of Port Huron	42,476	572 sq mi
(1,481 km2)	State map highlighting Gratiot County
Hillsdale County	059	Hillsdale	1829	From unorganized territory.	From its terrain, made up of hills and dales.[10]	46,688	607 sq mi
(1,572 km2)	State map highlighting Hillsdale County
Houghton County	061	Houghton	1845	From parts of Marquette County and Ontonagon County.	Dr. Douglass Houghton (1809-1845), first state geologist of Michigan, physician and surgeon, mayor of Detroit (1842-1843)	36,628	1,502 sq mi
(3,890 km2)	State map highlighting Houghton County
Huron County	063	Bad Axe	1840	From part of Sanilac County.	Lake Huron, which the French named lac des Hurons after the Hurons.	33,118	2,136 sq mi
(5,532 km2)	State map highlighting Huron County
Ingham County	065	Mason	1829 (boundaries declared)
1838 (organized)	From parts of Shiawassee County, Washtenaw County and unorganized territory.	Samuel D. Ingham (1779-1860), U.S. Secretary of the Treasury in the Jackson Administration	280,895	561 sq mi
(1,453 km2)	State map highlighting Ingham County
Ionia County	067	Ionia	1831	From part of Mackinac County and unorganized territory.	Province in ancient Greece	63,905	580 sq mi
(1,502 km2)	State map highlighting Ionia County
Iosco County	069	Tawas City	1840	From unorganized territory. Was named Kanotin County until 1843.	Schoolcraft pseudo-Native American name	25,887	1,891 sq mi
(4,898 km2)	State map highlighting Iosco County
Iron County	071	Crystal Falls	1885	From parts of Marquette County and Menominee County.	For the iron deposits and mines found in the county	11,817	1,211 sq mi
(3,136 km2)	State map highlighting Iron County
Isabella County	073	Mt. Pleasant	1831	From part of Mackinac County and unorganized territory.	Queen Isabella I (1451-1504) of Spain, under whose patronage Columbus undertook his voyages.	70,311	578 sq mi
(1,497 km2)	State map highlighting Isabella County
Jackson County	075	Jackson	1829 (boundaries declared)
1832 (organised)	From part of Washtenaw County and unorganized territory.	Andrew Jackson (1767-1845), 7th President of the United States and President when Michigan was admitted to the Union	160,248	724 sq mi
(1,875 km2)	State map highlighting Jackson County
Kalamazoo County	077	Kalamazoo	1829	From unorganized territory.	Named for the Kalamazoo River. See Etymology of Kalamazoo for a discussion of the river's name.	250,331	580 sq mi
(1,502 km2)	State map highlighting Kalamazoo County
Kalkaska County	079	Kalkaska	1840	From part of Mackinac County. Was named Wabassee County until 1843.	Schoolcraft pseudo-Native American name	17,153	571 sq mi
(1,479 km2)	State map highlighting Kalkaska County
Kent County	081	Grand Rapids	1831	From part of Mackinac County and unorganized territory.	New York jurist James Kent, who represented the Michigan Territory in its dispute with Ohio over the Toledo Strip.	602,622	872 sq mi
(2,258 km2)	State map highlighting Kent County
Keweenaw County	083	Eagle River	1861	From part of Houghton County.	Ojibwe word gakiiwe-wewaning meaning "portage"	2,156	5,966 sq mi
(15,452 km2)	State map highlighting Keweenaw County
Lake County	085	Baldwin	1840	From part of Mackinac County. Was named Aischum County until 1843.	Has several small lakes and lies near Lake Michigan	11,539	575 sq mi
(1,489 km2)	State map highlighting Lake County
Lapeer County	087	Lapeer	1822	From parts of Oakland County and St. Clair County.	An Americanization of the French la pierre, meaning "the rock" (flint)	88,319	663 sq mi
(1,717 km2)	State map highlighting Lapeer County
Leelanau County	089	Suttons Bay Township	1840	From part of Mackinac County.	Schoolcraft pseudo-Native American name	21,708	2,532 sq mi
(6,558 km2)	State map highlighting Leelanau County
Lenawee County	091	Adrian	1822	From part of Monroe County.	A Schoolcraft pseudo-Native American name for man, from either the Delaware leno or lenno or the Shawnee lenawai	99,892	761 sq mi
(1,971 km2)	State map highlighting Lenawee County
Livingston County	093	Howell	1833 (boundaries declared)
1836 (organized)	From parts of Shiawassee County and Washtenaw County.	Edward Livingston (1764-1836): second Secretary of State in the Andrew Jackson administration	180,967	585 sq mi
(1,515 km2)	State map highlighting Livingston County
Luce County	095	Newberry	1887	From parts of Chippewa County and Mackinac County.	Named for Michigan Governor Cyrus G. Luce	6,631	1,912 sq mi
(4,952 km2)	State map highlighting Luce County
Mackinac County	097	St. Ignace	1818	From part of Wayne County. Was named Michilimackinac County until 1837.	Originally Michilimackinac, believed to be a French interpretation of the Native American name for Mackinac Island, meaning "big turtle"	11,113	2,101 sq mi
(5,442 km2)	State map highlighting Mackinac County
Macomb County	099	Mt. Clemens	1818	From part of Wayne County.	Named for U.S. General Alexander Macomb, a notable officer of the War of 1812	840,978	570 sq mi
(1,476 km2)	State map highlighting Macomb County
Manistee County	101	Manistee	1840	From part of Mackinac County.	Named for the Manistee River, which in turn is from the Ojibwe name, ministigweyaa meaning "(river) at whose mouth there are islands"	24,733	1,281 sq mi
(3,318 km2)	State map highlighting Manistee County
Marquette County	103	Marquette	1843	From parts of Chippewa County and Mackinac County.	Named for French Jesuit missionary Jacques Marquette	67,077	3,425 sq mi
(8,871 km2)	State map highlighting Marquette County
Mason County	105	Ludington	1840	From part of Mackinac County. Was named Notipekago County until 1843.	Named for Michigan Governor Stevens T. Mason	28,705	1,242 sq mi
(3,217 km2)	State map highlighting Mason County
Mecosta County	107	Big Rapids	1840	From parts of Mackinac County and Oceana County.	Named for Mecosta, a Native American leader	42,798	571 sq mi
(1,479 km2)	State map highlighting Mecosta County
Menominee County	109	Menominee	1861	From part of Delta County. Was named Bleeker County until 1863.	Named for the Menominee Native American people	24,029	1,338 sq mi
(3,465 km2)	State map highlighting Menominee County
Midland County	111	Midland	1831	From part of Saginaw County and unorganized territory.	Located near the geographical center of the Lower Peninsula	83,629	528 sq mi
(1,368 km2)	State map highlighting Midland County
Missaukee County	113	Lake City	1840	From part of Mackinac County.	Named for Missaukee, an Ottawa leader who signed land-grant treaties in 1831 and 1833	14,849	574 sq mi
(1,487 km2)	State map highlighting Missaukee County
Monroe County	115	Monroe	1817	From part of Wayne County.	Named for James Monroe, the fifth U.S. President	152,021	680 sq mi
(1,761 km2)	State map highlighting Monroe County
Montcalm County	117	Stanton	1831	From part of Mackinac County and unorganized territory.	Named for Louis-Joseph de Montcalm, a French military commander in Quebec	63,342	721 sq mi
(1,867 km2)	State map highlighting Montcalm County
Montmorency County	119	Atlanta	1840	From part of Mackinac County and unorganized territory. Was named Cheonoquet County until 1843.	House of Montmorency, influential in the history of French Canada	9,765	562 sq mi
(1,456 km2)	State map highlighting Montmorency County
Muskegon County	121	Muskegon	1859	From parts of Oceana County and Ottawa County.	Muskegon River running through county, from the Ojibwa/Chippewa word mashkig meaning "swamp" or "marsh."	172,188	1,459 sq mi
(3,779 km2)	State map highlighting Muskegon County
Newaygo County	123	White Cloud	1840	From parts of Mackinac County and Oceana County.	Named for a Chippewa leader who signed the Saginaw Treaty of 1819[11]	48,460	861 sq mi
(2,230 km2)	State map highlighting Newaygo County
Oakland County	125	Pontiac	1819 (boundaries declared)
1820 (organized)	From part of Macomb County.	The numerous "oak openings" in the area: "majestic orchard[s] of oaks and hickories varied by small prairies, grassy lawns and clear lakes"[12]	1,202,362	908 sq mi
(2,352 km2)	State map highlighting Oakland County
Oceana County	127	Hart	1831	From part of Mackinac County.	Borders Lake Michigan, the freshwater "ocean."	26,570	1,307 sq mi
(3,385 km2)	State map highlighting Oceana County
Ogemaw County	129	West Branch	1840	From unorganized territory. Annexed to Iosco County in 1867 and reinstated in 1873.	The Ojibwe word ogimaa, meaning "chief" or "leader"	21,699	575 sq mi
(1,489 km2)	State map highlighting Ogemaw County
Ontonagon County	131	Ontonagon	1843	From parts of Chippewa County and Mackinac County.	Named for the Ontonagon River. The Ojibwa word onagon means "dish" or "bowl."	6,780	3,741 sq mi
(9,689 km2)	State map highlighting Ontonagon County
Osceola County	133	Reed City	1840	From part of Mackinac County. Was named Unwattin County until 1843.	Osceola (1804-1838), Seminole chief	23,528	573 sq mi
(1,484 km2)	State map highlighting Osceola County
Oscoda County	135	Mio	1840	From part of Mackinac County and unorganized territory.	Schoolcraft pseudo-Native American name	8,640	572 sq mi
(1,481 km2)	State map highlighting Oscoda County
Otsego County	137	Gaylord	1840	From part of Mackinac County. Was named Okkudo County until 1843.	Named for Otsego County, New York	24,164	526 sq mi
(1,362 km2)	State map highlighting Otsego County
Ottawa County	139	Grand Haven	1831	From part of Mackinac County and unorganized territory.	Named for the Native American Ottawa people.	263,801	1,632 sq mi
(4,227 km2)	State map highlighting Ottawa County
Presque Isle County	141	Rogers City	1840	From part of Mackinac County.	A derivation of the French phrase for "peninsula", literally "almost an island."	13,376	2,573 sq mi
(6,664 km2)	State map highlighting Presque Isle County
Roscommon County	143	Roscommon	1840	From part of Mackinac County and unorganized territory. Was named Mikenauk County until 1843.	County Roscommon, Ireland	24,449	580 sq mi
(1,502 km2)	State map highlighting Roscommon County
Saginaw County	145	Saginaw	1822	From part of Oakland County.	A Native American term, perhaps a reference to the Saginaw River and Saginaw Bay, Ojibwe for "at the outlet" [13]	200,169	816 sq mi
(2,113 km2)	State map highlighting Saginaw County
St. Clair County	147	Port Huron	1820	From part of Macomb County.	Named for either Arthur St. Clair, first governor of the Northwest Territory, or Saint Clair on whose feast day Lake St. Clair was discovered	163,040	837 sq mi
(2,168 km2)	State map highlighting St. Clair County
St. Joseph County	149	Centreville	1829	From unorganized territory.	The St. Joseph River, which flows through the county.[14]	61,295	521 sq mi
(1,349 km2)	State map highlighting St. Joseph County
Sanilac County	151	Sandusky	1822	From part of St. Clair County.	Sanilac, a Wyandotte chief	43,114	1,590 sq mi
(4,118 km2)	State map highlighting Sanilac County
Schoolcraft County	153	Manistique	1843	From parts of Chippewa County and Mackinac County.	Henry Rowe Schoolcraft, (1793-1864):
American geographer and Superintendent of Indian Affairs in Michigan	8,485	1,884 sq mi
(4,880 km2)	State map highlighting Schoolcraft County
Shiawassee County	155	Corunna	1822	From parts of Oakland County and St. Clair County.	Named for the Shiawassee River, and means 'river that twists about.[15]	70,648	541 sq mi
(1,401 km2)	State map highlighting Shiawassee County
Tuscola County	157	Caro	1840	From part of Sanilac County.	Pseudo-Native American name created by Henry Schoolcraft	55,729	914 sq mi
(2,367 km2)	State map highlighting Tuscola County
Van Buren County	159	Paw Paw	1829	From unorganized territory.	Martin Van Buren (1782-1862): Secretary of State in the Jackson Administration, later Vice President and eighth President of the United States	76,258	1,090 sq mi
(2,823 km2)	State map highlighting Van Buren County
Washtenaw County	161	Ann Arbor	1822 (boundaries declared)
1826 (organised)	From parts of Oakland County and Wayne County	From the Native American name for the Grand River, O-wash-ta-nong ("faraway water"),[16] whose headwaters were within the county's bounds.	344,791	723 sq mi
(1,873 km2)	State map highlighting Washtenaw County
Wayne County	163	Detroit	1815	All lands within Michigan Territory that had been ceded by Native Americans through the 1807 Treaty of Detroit.	"Mad" Anthony Wayne, (1745-1796):
United States Army general and statesman	1,820,584	672 sq mi
(1,740 km2)	State map highlighting Wayne County
Wexford County	165	Cadillac	1840	From part of Mackinac County. Was named Kautawaubet County until 1843.	County Wexford, Ireland	32,735	576 sq mi
(1,492 km2)	State map highlighting Wexford County