Early visitors to Indiana County were settlers and traders of the East-West Kittanning Trail, a trail led by Colonel John Armstrong during the Kittanning Expedition of the French & Indiana War in 1756. Peacetime with the Native Americans was reached largely through the Purchase of 1776, in which the Great Nations ceded the land south of “Purchase Line” - freeing the land for settlement.
Indiana County was officially created by the Pennsylvania Legislature in March of 1803 from parts of Westmoreland and Lycoming Counties. With the formation of the new county, competition developed between various areas for the honor of becoming the county seat. This was settled in 1805 as George Clymer, a signer of both the Declaration of Independence and the Constitution, donated 250 acres of his own land in the center of the county to be used as a county seat. This area grew to become the town of Indiana.
According to the Census of 1810, Indiana County had a population of 6,214. In 1816, the same year Pittsburgh was incorporated as a city, the town of Indiana officially became a borough. Official business of the County was transferred from Greensburg and the first session of the Indiana County Court was held on the second floor of Peter Sutton's Tavern (where The Coney bar and restaurant is located today). Three years later in 1819, the first Court House was built (where First Commonwealth Bank is headquartered today).
In the 1830's and 1840's, Indiana County became a hotbed of abolitionism. The Center Township Anti-Slavery Society was organized in 1838 and an abolition newspaper, The Clarion Freedom, was established in 1843. The county was on one of the mail lines of the Underground Railroad and prominent citizens risked their lives by harboring runaway slaves. A fervent Indiana abolitionist, Dr. Robert Mitchell, was convicted and fined by a Federal Court in 1847 for helping slaves. During the Civil War, Indiana County sent several regiments of troops to fight for the Union.
In 1855, a Normal School for training teachers began in the old Indiana Academy and in the basement of a local church. Later, a movement started for the founding of a state Normal School, which bore fruit in 1875 as the Indiana State Normal School. Over the years, the school’s name changed as it grew, from Indiana State Teachers College in 1920 - when it was awarded the right to grant degrees; to Indiana State College in 1959; and finally to Indiana University of Pennsylvania (IUP) in 1965 - when it offered its first doctoral program. It is the only school in the State System to offer graduate instruction at the doctoral level (PhD).
From frontier wilderness in the eighteenth century, Indiana experienced initial growth as an agricultural economy and prospered later as an energy center in the modern era. Today, Indiana County thrives on an economic base combining agriculture, commerce, education, and energy production to provide an outstanding quality of life for its nearly 85,000 residents. Indiana also remains a recreation mecca with a major state park, five county parks and eight state game lands abounding in wildlife.
More history is available through the Historical and Genealogical Society of Indiana County.