Barren County was founded by act of the General Assembly in 1798, the sixth year of the Commonwealth. The county, which at that time included a large part of the present counties of Hart, Metcalfe, Monroe and Allen in addition to present Barren County, had no towns or villages. Two sites were considered for the county seat because of their central location and water supplies, John Gorin's Spring and Squire Garnett's Spring at the Long Hunters Camp. The residents in the county chose the Gorin site, taking two days to vote, Gorin's Revolutionary comrades being the deciding factor.
The name Glasgow is attributed to John Matthews, one of the early pioneers in the county. Matthews was a native of Scotland and tradition states that the town was named by him in honor of his birthplace. He certainly was active in the early history of the town, being employed by the court to clear the square and in addition held almost every office in the county at one time or the other.
From the outset the town became a center of commerce and travel due to the early highways crossing here, a extension of the Wilderness Road, U.S. 68 and an extension of the Natchez Trace, U.S. 31E. The coming of the railroad in the 1870's increased commerce even more.
In September 1853 the city was struck by its greatest disaster, Asiatic cholera, which threatened to wipe out the populace. The disease was brought to Glasgow by a traveling circus and the big spring, main water source for the city soon became polluted, infecting members of almost every family in town. Some fled, but many stayed to nurse the sick and bury the dead until the disease had run its course.
Although Confederate in sympathy, Glasgow was a Union garrison during most of the Civil War. It was the scene of two short but lively actions, Morgan's Christmas Raid in December 1862 and the fall of Fort Williams to the Confederates in October 1863.
Glasgow became an incorporated city in 1878, holding its first city council meeting on May 6, 1878. In 1958 Glasgow became a third-class city.