French explorers had longstanding claims to the area which they acted to secure in an unambiguous fashion with a military-Amerindian expedition in 1749 that buried a succession of plaques claiming the territory as France's in response to the formation of the colonial Ohio Company—and the first of these was buried in Warren[6] but ultimately control was transferred to the British after the French and Indian War.

After the Revolutionary War, General William Irvine and Andrew Ellicott were sent to the area to lay out a town in 1795.

[7] The first permanent structure in Warren, a storehouse built by the Holland Land Company, was completed in 1796.

David Beaty discovered oil in Warren in 1875 while drilling for natural gas in his wife's flower garden.

Many of the town's large Victorian homes were built with revenue generated by the local oil and timber industries.

Several miniature replicas are located within the county, including one at the new visitors center on Routes US 6 and US 62[10] next to the Pennsylvania State Police barracks.

Warren has struggled through hard economic times and a steady decline in population, which peaked at nearly 15,000 in 1940.

The completed project will include new townhouses and senior citizen housing, retail and commercial development, a parking garage, convention center and bus depot.

[citation needed] Major employers include Walmart, the United Refining Company (gas supplier for Kwik Fill and Red Apple Food Mart gas stations), Allegheny National Forest, Northwest Bank, Whirley-Drinkworks, Superior Tire and Rubber Corp, Pennsylvania General Energy, Betts Industries, Inc, Blair Corporation, Sheetz, and Interlectric.

The Allegheny River from the Kinzua Dam to the City of Warren has been designated a "Recreational Waterway" by the United States Congress.

[21] The Warren teams played home minor league games at Russell Park.