Middletown was settled in 1752, when George Fisher arrived from Philadelphia and built a home on the west bank of Swatara Creek. Named Middletown because it was midway between Lancaster and Carlisle, this oldest town in Dauphin County became incorporated as a borough in 1826. Through the years Middletown became noted for its Wincroft Stove Works, Standard Steel Car Company, Middletown-Royalton Brick Works, and Rough Wear Clothing Company. During World War II, Olmsted Air Force Base added greatly to the town's economy. In 1979, the Three Mile Island nuclear incident assured that Middletown would be known to the rest of the world.