Known in early days as "McAllisterstown" (for founder Colonel Richard McAllister) and "Rogue's Harbor" (for lack of law enforcement), Hanover is in the rich Conewago Valley. Here, on June 30, 1863, Confederate General J. E. B. Stuart's cavalry tangled with Union forces under Generals Kilpatrick and Custer. The battle prevented Stuart from reaching Gettysburg in time to function as "the eyes of Lee's army."

Among the products of the town's diversified industry are books, wirecloth, yarns, furniture, industrial machinery, textiles, and foods, including the famous pretzel maker, Snyder's of Hanover.