It was named to honor William Taylor Barry, who was serving as United States Postmaster General at the time of the county's proclamation.

In 1839, the Michigan State Legislature approved the organization of Barry County as an independent entity.

In the early years of the twentieth century, petroleum deposits of varying magnitudes were discovered and developed in Michigan's Lower Peninsula.

[6] The only railroad left in the county is a two-mile section owned by CSX Transportation, running through the northeastern corner of Woodland Township.

[14] As of the 2000 United States Census,[15] there were 56,755 people, 21,035 households, and 15,986 families living in the county.

The county government operates the jail, maintains rural roads, operates the major local courts, records deeds, mortgages, and vital records, administers public health regulations, and participates with the state in the provision of social services.

The county board of commissioners controls the budget, and has limited authority to make laws or ordinances.

In Michigan, most local government functions—police and fire, building and zoning, tax assessment, street maintenance, etc.—are the responsibility of individual cities and townships.

(information as of December 2012[update]) In an October 2020 interview with Fox 17 News, Sheriff Dar Leaf stated that the individuals charged in a plot to kidnap Governor Gretchen Whitmer may have been attempting to effectuate a lawful arrest on Whitmer as opposed to a kidnapping.

The annual Barry County Artists Exhibition highlights local art each summer.