Preble County's flag was designed by Mr. Travis Lee of Preble County, Ohio and designated as Preble County's flag by Preble County Commission Resolution#656-02-102 adopted November 6, 2002. The Preble County Board of Commissioners, in conjunction with the Preble County Historical Society, sponsored a contest to design a new flag for Preble County in commemoration of Ohio's Bicentennial in 2003. On July 5-6, 2002, seventeen entries were displayed at the Preble County Ohio Bicentennial Bell Casting and Old Fashioned Independence Day Celebration to allow the public to vote for its preferred design. After calculating the votes, the top three selections were presented to the Board of Preble County Commissioners for their review and consideration. Because it contained elements of historical significance and county relevance, capturing the essence of Preble County's pride and distinct agricultural history, the Board of Preble County Commissioners selected a flag designed by Travis Lee of Preble County, Ohio. In the center of the flag is a circular seal surrounded by twelve white stars symbolizing the twelve townships in Preble County. The distinguished Roberts Bridge, the oldest double-barreled covered bridge in the United States, is featured on the seal, representing Preble County's celebrated covered bridges. Within the seal, Preble County's agricultural roots are depicted by lush green plains, crops and farm buildings on the horizon. A silhouette of Fort St. Clair lies in the distance, paying tribute to the Preble County's famous battleground. The seal also includes a pair of swine referencing the renowned Preble County Pork Festival and Preble County's long legacy of pork production. Clustered at the base of the seal is an apple, corn stalk, soybean sheaf, musket, powder horn, coonskin cap, and lance-all of which allude to the Preble County's frontier heritage. This flag takes the place of a previous 1976 Preble County flag by Diane A. Lohrey, which was never officially adopted. Preble County was established in 1808, and named for Captain Edward Preble, a naval commander in the Revolutionary War and the War with Tripoli.
