Barrow was created in 1914 as a way of settling a dispute among the citizens of the City of Winder, which at the time was located at the juncture of three counties. A new county was created from parts of Gwinnett, Jackson, and Walton counties, with Winder designated as the county seat. The new county was named for David Crenshaw "Uncle Dave" Barrow, long-time chancellor of the University of Georgia.

Winder was incorporated in 1893 when the Seaboard Air Line Railroad was built through the town. It was named after the president of the railroad, John H. Winder of North Carolina. Richard B. Russell, Jr., who served as governor of Georgia and as U.S. Senator from 1933 to 1971, was from Barrow County. His father, Richard Russell, Sr., was Chief Justice of the Georgia Supreme Court from 1922-1938 and swore in his son as governor.