An engraving of Colonel Ulric Dahlgren, based on an earlier photograph by Mathew Brady, illustrates a Harper's Weekly article that recounts the young Union officer's death. Twenty-one-year-old Dahlgren, still recovering from the amputation of one of his legs, was killed in early March 1864 while taking part in an ambitious mission led by the flamboyant general H. Judson Kilpatrick. The plan was to infiltrate the Confederate capital and free captives from Libby and Belle Isle prisons, but reports of the approaching Union cavalry led Confederate authorities to take extreme measures. A mine was dug in Libby Prison's basement and filled with 200 pounds of gunpowder; if any inmates attempted to escape, officials were prepared to blow up the prison. The Confederate Congress approved of the tactic. "Had the prisoners escaped, the women and children of the city, as well as their homes, would have been at the mercy of 5,000 outlaws," a congressional committee wrote in a March 3, 1865 report. "Humanity required that the most summary measures should be used to deter them from any attempt at escape."
Dahlgren was killed during a nighttime ambush by Confederate forces and his body was brought to Richmond where it was exposed to public view for some hours and was then buried "in a common pine coffin in some place unknown to any but the rebel authorities," according to Harper's Weekly. Papers found on his body suggested that his orders might have extended to assassinating Confederate president Jefferson Davis and torching the city, though federal officials denied such a plan. Richmond resident and Union informant, Elizabeth Van Lew, was so outraged over reports that Dahlgren's corpse had been handled disrespectfully that she risked exposing her own covert spying operation when she had his body surreptitiously exhumed and properly reburied.