Barbara is a 90-year-old widow and resident of Frederick, Maryland, who possesses staunch Unionist beliefs. Despite her age and stooped posture, she maintains immense courage and patriotic conviction. She refuses to appease the invading Confederate army, choosing instead to risk her physical safety by proudly displaying the United States flag from her attic window.

Jackson is a prominent Confederate general leading forces through Maryland during the Civil War. Though initially presenting a stern military threat by ordering his men to shoot the Union flag from Barbara's window, he quickly proves capable of humility and chivalry. He respects true courage and honors integrity even in those who oppose his army.

General Robert E. Lee is the commander of the Confederate Army of Northern Virginia. He leads an invasion into Maryland in September 1862, hoping to recruit young men to reinforce his hungry troops. He issues a proclamation to the people of Maryland, though he finds little enthusiasm among the citizens of Frederick.

Mary Quantrill is a resident of Frederick who operates a private school. Like Barbara, she is a brave and loyal Unionist who waves small flags at the passing rebel soldiers alongside her students, earning the grudging respect of a Confederate officer who protects her from harm.