Early settlers and traders of the East-West Kittanning Trail were the initial visitors to Indiana County. It was along the Kittanning Trail that Colonel John Armstrong led the Kittanning Expedition of the French & Indiana War in 1756. Peace with the Native Americans was ultimately reached largely through the Purchase of 1776, in which the Great Nations ceded the land south of “Purchase Line” - marking the land free 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 among various areas for the honor of becoming the county seat. This was settled in 1805 when George Clymer of Philadelphia, a signer of both the Declaration of Independence and the Constitution, donated 250 acres of his land in the center of the county to be used as a county seat. This area became the town of Indiana.
In 1816, official business of the county was transferred from Greensburg when the first session of the Indiana County Court was held on the second floor of Peter Sutton's Tavern (where The Coney is located today). Three years later, the first Court House was built (where First Commonwealth Bank is headquartered today). According to the census of 1810, Indiana County had a population of 1,214. The first newspaper was started in 1814 and hewed to the Federalist line in politics. The town of Indiana officially became a borough in 1816, the same year Pittsburgh was incorporated as a city.
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 many prominent citizens risked their lives by harboring runaway slaves. A fervent Indiana abolitionist, Dr. Robert Mitchell, was convicted by a Federal Court in 1847, and fined 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 church. A movement had started around 1870 for the founding of a state Normal School, which bore fruit in 1875 when Indiana State Normal School was established. It became a four-year State Teacher's College in 1927, and began granting degrees. The Normal School transformed into Indiana University of Pennsylvania (IUP) - the second largest accredited state-school in the Commonwealth today.
From frontier wilderness in the eighteenth century, Indiana County had its initial growth as an agricultural county and prospered as an energy center in the modern era. Today, Indiana County thrives with an economic base combining education, agriculture, energy production and commerce into an outstanding quality of life for its nearly 85,000 residents.
It is uniquely both the Christmas Tree Capital of the World and a major national center for energy production. More than 12,000 students study a variety of disciplines at the Indiana University of Pennsylvania, while in Smicksburg the Amish continue their traditional lifestyle. The County 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.