During the territorial period the one large county of Knox, originally as large as the present state, was divided and re-divided until thirteen counties covered the various land purchases that the United States had secured prior to 1816. By the re-dividing process, these counties as originally formed, had but little correspondence with the subsequent divisions that continued to bear their names given. The formations in chronological order were:

Clark County detached from Knox by act of February 3, 1801.

Dearborn, out of Clark, March 7, 1803.

Harrison, out of Knox and Clark, October 11, 1808.

Jefferson, out of Clark and Dearborn, November 23, 1810.

Franklin, out of Dearborn and Clark, November 27, 1810.

Wayne, out of Dearborn and Clark, November 27, 1810.

Warrick, out of Knox, March 9, 1813.

Gibson, out of Knox, March 9, 1813

Washington, out of Harrison and Clark, December 21, 1813.

Posey, out of Warrick, September 7, 1814.

Perry, out of Gibson and Warrick, September 7, 1814.

Switzerland, out of Dearborn and Jefferson, September 7, 1814.

The chief towns that had sprung up and the dates of their founding were:

Vincennes, 1732 (long a disputed question, but this date now accepted); Jeffersonville, 1802; Lawrenceburg, 1802; Brookville, 1807; Corydon, 1808; Charlestown, 1808; Salisbury, 1810; Madison, 1812; New Albany, 1813; Vevay, 1813; Salem, 1814; Centerville, 1814; Rising Sun, 1814; Brownstown, 1815; Richmond, 1816 (Baskin & Forster Atlas, 1876), Vallonia, Springville Clarksville and other small places, some of them long since extinct, also belong to this period.