Ulric Dahlgren, American colonel (b. 1842)
Ulric Dahlgren (April 3, 1842 – March 2, 1864) was a colonel in the Union Army during the American Civil War. He was the son of Union Navy Rear Admiral John A. Dahlgren and nephew to Confederate Brigadier General Charles G. Dahlgren.

He fought in several key battles in the Eastern Theater of the American Civil War and had his leg amputated below the knee after being wounded at the Battle of Gettysburg. He returned to military service and was killed in 1864 during the Battle of Walkerton while leading a raid on the Confederate capital of Richmond, Virginia.

Confederate forces found documents on Dahlgren with orders to free Union prisoners from Belle Isle, burn the city of Richmond and assassinate Confederate President Jefferson Davis and his cabinet. The documents were published in the Richmond newspapers and caused outrage in the South with accusations that the orders came from President Lincoln. Union newspapers claimed the papers were forged and reports of mistreatment of Dahlgren's corpse inflamed public opinion in the North. The controversy became known as the Dahlgren Affair.