Dearborn County was created from Clark County in the Indiana Territory (pre-statehood) in 1803. See the Executive Journal of Indiana Territory, 1800-1816, p. 116. Available at Google Books. Also, online at Ancestry (https://www.ancestry.com/search/collections/22378/). It became a county in the state of Indiana when Indiana gained statehood in 1816. Ripley county was formed from Dearborn County in 1818. Ohio County was formed from portions of Dearborn in 1845.
Dearborn County, Indiana, holds a rich history dating back to its formation in 1803. Situated on the Ohio border near the southeast corner of the state, it was carved out of a portion of Hamilton County, Ohio. The county’s establishment was closely tied to the shifting territorial boundaries following Ohio’s admission to the Union in 1803. In the case of Dearborn County, the “Gore” comprised a portion of the land along Ohio’s southwestern border, and it was ceded to the Indiana Territory in 1803 following Ohio’s admission to the Union. This wedge or pie-shaped area became an integral part of the newly formed Dearborn County. The Gore is not exclusive to Dearborn County but extends into several present-day counties, including Dearborn, Franklin, Ohio, Randolph, Switzerland, Union, Wayne, and Fayette. Researchers will not want to miss the website Indiana’s Gore – Genealogy Resources, https://www.indianasgore.com/.
Dearborn County was named for Dr. Henry Dearborn (1751-1829). Dearborn served as Secretary of War from 1801-1809 under President Thomas Jefferson. Lawrenceburg was designated as the county seat. Early growth in the area centered around Lawrenceburg, which became a crucial railroad junction connecting major rail lines in the region. The present boundaries were established in 1845.
According to the 2010 census, Dearborn County covers a total area of 307.42 square miles, with 99.22% being land and 0.77% water. The Ohio River forms part of the southeastern county line.
Record Loss
A courthouse fire in 1826 destroyed most records. Some marriage and will records survived the fire. See the transcription of an article that appeared in the (Lawrenceburg) Indiana Palladium, 18 Mar 1826, p. 3, col. 1, https://www.indianasgore.com/dearborn-county-1826-courthouse-fire/.
