| Year |
Follow this LINK to watch the progression of county formations from 1600 to the present. |
Treaties |
| 1781 |
|
Clark’s Grant |
| 1783 |
|
Vincennes Tract |
| 1790 |
Knox, St. Clair (IL) formed as original counties of Northwest Territory. |
|
| 1795 |
Randolph (IL) from St. Clair. |
Treaty of Greenville |
| 1796 |
Wayne (MI) from Knox. |
|
| 1798 |
Hamilton (OH) gained from Knox. |
|
| 1800 |
Indiana Territory formed from Northwest Territory. |
|
| 1801 |
Clark from Knox. St. Clair gained from Knox. |
|
| 1803 |
Dearborn from Clark (after Clark gained from Northwest Territory). |
First Treaty of Fort Wayne |
| |
Wayne County, Indiana Territory, formed as successor to Wayne County, Northwest Territory, with additions from Knox, St. Clair, non-county area. |
|
| 1804 |
|
Treaty of Vincennes |
| 1805 |
Michigan Territory formed from Indiana Territory. |
Treaty of Grouseland |
| 1808 |
Harrison from Knox, Clark. |
|
| 1809 |
Illinois Territory formed from Indiana Territory. |
Second Treaty of Fort Wayne |
| 1810 |
Harrison gained from Clark. |
|
| 1811 |
Franklin from Dearborn, Clark. |
|
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Wayne from Dearborn, Clark, Knox. |
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Jefferson from Clark, Dearborn, Knox. |
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| 1813 |
Gibson from Knox. |
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Warrick from Knox. |
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| 1814 |
Posey from Warrick, Gibson. |
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Posey from Warrick. |
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Switzerland from Dearborn, Jefferson. |
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Washington from Clark, Harrison, Knox. |
|
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Dearborn gained from Jefferson. |
|
| 1816 |
Indiana admitted as a state. |
|
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Jackson from Washington, Clark, Jefferson. |
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Orange from Washington, Knox, Gibson. |
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Ripley from Dearborn, Jefferson. |
|
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Posey gained from Gibson. |
|
| 1817 |
Daviess from Knox. |
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Jennings from Jefferson, Jackson. |
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Pike from Gibson, Perry. |
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Sullivan from Knox. |
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Posey gained from Gibson. |
|
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Knox lost to non-county area. |
|
| 1818 |
Dubois from Pike. |
Treaty of St. Mary’s |
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Crawford from Orange, Harrison, Perry. |
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Lawrence from Orange. |
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Monroe from Orange. |
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Randolph from Wayne. |
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Vigo from Sullivan. |
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Spencer from Warrick, Perry. |
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Vanderburgh from Gibson, Posey, Warrick. |
|
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Orange gained from Harrison. |
|
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Ripley organized. |
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| 1819 |
Fayette from Wayne, Franklin, non-county area. |
|
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Floyd from Harrison, Clark. |
|
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Owen from Daviess, Sullivan. |
|
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Wayne, Jackson gained from non-county area. |
|
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Vigo gained from Sullivan. |
|
| 1820 |
Delaware New Purchase from non-county area. |
|
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Unorganized, attached concurrently to Fayette, Franklin, Jackson, Jennings, Randolph, Ripley, Wayne. |
|
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Wabash New Purchase from non-county area. |
|
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Unorganized, attached concurrently to Monroe, Vigo, Owen. |
|
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Martin from Daviess, Dubois. |
|
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Scott from Clark, Jefferson, Jennings, Jackson, Washington. |
|
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Franklin, Randolph gained from non-county area. |
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Jennings gained from Jackson, non-county area. |
|
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Daviess lost to non-county area. |
|
| 1821 |
Bartholomew from Jackson, Delaware New Purchase. |
Treaty of Chicago |
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Greene from Sullivan, non-county area. |
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Parke from Vigo, Wabash New Purchase, non-county area. |
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Union from Wayne, Franklin, Fayette. |
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Daviess gained from non-county area. |
|
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Wayne, Monroe gained from Delaware New purchase. |
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Floyd gained from Clark. |
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Monroe gained from Owen. |
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Owen gained from Monroe, Wabash New Purchase. |
|
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Change in attachment of Delaware New Purchase, Wabash New Purchase. |
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| 1822 |
Decatur, Henry, Marion, Rush, Shelby from Delaware New Purchase. |
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Morgan from Delaware New Purchase, Wabash New Purchase. |
|
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Putnam from Own, Wabash New Purchase. |
|
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Gibson gained from Posey. |
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Ripley gained from Switzerland. |
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Change in attachments of Delaware New Purchase, Wabash New Purchase. |
|
| 1823 |
Hamilton, Johnson, Madison from Delaware New Purchase. |
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Montgomery from Wabash New Purchase. |
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Lawrence gained from Jackson. |
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Posey gained from Gibson. |
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Floyd gained from Harrison. |
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Henry gained from Wayne. |
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| 1824 |
Allen from Delaware New Purchase, non-county area. |
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Hendricks from Delaware New Purchase, Wabash New Purchase. |
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Vermillion from Parke, Wabash New Purchase, non-county area. |
|
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Delaware New Purchase exchanged with Randolph. |
|
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Parke gained from Montgomery, Putnam. |
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Wayne gained from Henry. |
|
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Gibson exchanged with Pike. |
|
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Harrison lost to non-county area. |
|
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Warrick gained from Gibson. |
|
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Changes in attachments of Wabash New Purchase, Delaware New Purchase, non-county area. |
|
| 1825 |
Clay from Owen, Putnam, Vigo, Sullivan. |
|
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Gibson gained from Pike. |
|
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Spencer gained from Warrick. |
|
| 1826 |
Fountain from Montgomery, Wabash New Purchase. |
Michigan Road |
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Tippecanoe from Wabash New Purchase, non-county area. |
Treaty of Mississinwas |
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Fayette, Union gained from Franklin. |
|
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Warrick gained from Pike. |
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Change in attachments of Delaware New Purchase, Wabash New Purchase. |
|
| 1827 |
Hancock from Madison. |
|
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Unorganized attached to Madison. |
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Delaware from Delaware New Purchase. |
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Warren from Wabash New Purchase, non-county area. |
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Delaware New Purchase name changed to Adams New Purchase. |
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Madison gained from Delaware new Purchase. |
|
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Crawford gained from Perry. |
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Henry gained from Wayne. |
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| 1828 |
Carroll from Adams New Purchase, Wabash New Purchase, non-county area. |
|
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Bartholomew, Jackson, Monroe gained from Adams New Purchase. |
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Martin gained from Daviess. |
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Floyd gained from non-county area. |
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Adams New Purchase lost to non-county area. |
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Change in attachments of Adams New Purchase, Wabash New Purchase, non-county area. |
|
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Hancock organized. |
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| 1829 |
Cass from non-county area. |
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Change in attachment of non-county area. |
|
| 1830 |
Boone from Adams new Purchase, Wabash New Purchase. |
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Clinton from Adams New Purchase, Wabash New Purchase. |
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Elkhart from non-county area. |
|
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Non-county area attachment changed from Allen to Elkhart. |
|
| 1831 |
Grant from Madison, Adams New Purchase, non-county area. |
|
| |
Marion gained from Hendricks. |
|
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Monroe gained from non-county area. |
|
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Change in attachments of areas of Adams New Purchase. |
|
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Change in attachments of non-county areas. |
|
| 1832 |
Huntington from Adams New Purchase, non-county area. |
Treaty of Tippecanoe |
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La Porte from St. Joseph, non-county area. |
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Miami from Cass, non-county area. |
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La Grange from non-county area. |
|
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St. Joseph gained from Elkhart. |
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Cass gained from non-county area. |
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Elkhart gained from non-county area. |
|
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Non-county area attachment changed from Elkhart. |
|
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Allen to La Grange. |
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| 1833 |
Vermillion gained from Warren. |
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| 1834 |
White from Wabash New Purchase, non-county ara. |
|
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Miami gained from Cass. |
|
| |
Huntington, Miami organized. |
|
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Part of Wabash New Purchase, non-county area attachment changed from Carroll to White. |
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Non-county area attachment changed from Warren, St. Joseph to White. |
|
| 1835 |
Adams from Adams New Purchase. |
|
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Unattached to Allen, Delaware, Randolph. |
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De Kalb from non-county area. |
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Unattached to Allen, La Grange. |
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Fulton from non-county area. |
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Unattached to Elkhart, Cass, St. Joseph. |
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Jasper from Wabash New Purchase, non-county area. |
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Unattached to Warren, White. |
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Jay from Adams New Purchase. |
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Unattached to Randolph, Delaware. |
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Kosciusko from non-county area. |
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Unattached to St. Joseph, Elkhart, Cass. |
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Marshal from St. Joseph. |
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Unattached to St. Joseph, Kosciusko, Cass. |
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Newton from non-county area. |
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Unattached to St. Joseph, Warren, White. |
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Noble from non-county area. |
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Unattached to Elkhart, La Grange, Allen. |
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Porter from non-county area. |
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Unattached to St. Joseph. |
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Pulaski from non-county area. |
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Unattached to Cass, White. |
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Starke from St. Joseph, non-county area. |
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Unattached to St. Joseph, White Cass. |
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Steuben from non-county area. |
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Unattached to La Grange. |
|
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Wells from Adams New Purchase. |
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Unattached to Allen, Delaware, Randolph. |
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Whitley from non-county area. |
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Unattached to Elkhart, Allen, La Grange. |
|
| |
Wabash organized. |
|
| |
Wabash New Purchase eliminated. |
|
| 1836 |
Brown from Monroe, Bartholomew, Jackson. |
Treaty of Yellow River |
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Lake from Porter, Newton. |
|
| |
Unorganized, attached to Porter. |
|
| |
Porter gained from Newton. |
|
| |
Clark exchanged with Jefferson. |
|
| |
Marshall gained from Elkhart, St. Joseph. |
|
| |
Noble, Porter, Adams, Jay, Kosciusko, Fulton, Marshall organized. |
|
| |
Whitley attachment changed from Allen, Grant, Elkhart to Huntington. |
|
| 1837 |
Jefferson gained from Clark. |
|
| |
Lake, DeKalb, Steuben, Wells organized. |
|
| 1838 |
Blackford from Jay. |
|
| |
Unorganized attached to Jay. |
|
| |
Elkhart, St. Joseph gained from Marshall. |
|
| |
Newton gained from Lake, Porter. |
|
| |
Madison gained disputed area from Grant. |
|
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Cass, Fulton, Miami, Wabash, White gained from non-county area. |
|
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Bartholomew lost to non-county area. |
|
| |
Jasper, Whitley organized. |
|
| 1839 |
Newton merged into Jasper, Lake, La Porte. |
|
| |
White gained from Carroll. |
|
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Marshall gained from Elkhart, St. Joseph. |
|
| |
Scott gained from Clark, Washington. |
|
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La Porte gained from non-county area. |
|
| |
Non-county areas attached to Carroll, Cass, Hamilton, Miami, Blackford. |
|
| |
Pulaski organized. |
|
| 1840 |
Benton from Jasper. |
Treaty of the Wabash |
| |
Fulton gained from Kosciusko. |
|
| 1841 |
Jasper gained from White. |
|
| 1842 |
Clark gained from Scott. |
|
| |
Clark exchanged with Washington. |
|
| |
La Porte gained from Starke. |
|
| |
Gibson gained from Warrick. |
|
| |
Kosciusko gained from Fulton. |
|
| |
Sullivan gained from Knox. |
|
| |
Warrick gained from Spencer. |
|
| |
Jackson gained from non-county area. |
|
| |
Carroll lost to non-county area. |
|
| 1844 |
Richardville from non-county area. |
|
| |
Ohio from Dearborn. |
|
| |
Tipton from Adams New Purchase, non-county area. |
|
| |
Adams New Purchase eliminated. |
|
| |
Floyd gained from Clark. |
|
| |
Warrick gained from Gibson. |
|
| |
Fulton gained from Miami. |
|
| 1845 |
Richardville gained from non-county area. |
|
| 1846 |
Richardville name changed to Howard. |
|
| |
Fulton gained from Kosciusko. |
|
| |
Clark exchanged with Washington. |
|
| |
Carroll gained from non-county area. |
|
| 1847 |
Gibson gained from Warrick. |
|
| 1850 |
La Porte gained from St. Joseph. |
|
| |
Starke organized. |
|
| 1851 |
Scott gained from Jefferson |
|
| 1852 |
Floyd gained from Harrison. |
|
| |
Warrick gained from Gibson. |
|
| 1853 |
Spencer gained from Warrick. |
|
| 1859 |
Newton re-created from Jasper. |
|
| |
Howard gained from Clinton. |
|
| |
Whitley gained from Noble. |
|
| |
Lawrence gained from Jackson. |
|
| 1861 |
Putnam gained from Morgan. |
|
| 1868 |
Hendricks gained from Morgan. |
|
| 1873 |
Clark exchanged with Washington. |
|