Union General Hugh Judson Kilpatrick's cavalry raiders split into two wings on their way south to Richmond. Colonel Ulrich Dahlgren and 500 troopers swung out further west as Kilpatrick and 3,000 men rode on to the outskirts of Richmond. The raid stalled there, and Dahlgren was killed in an ambush. The raid was part of a plan to free 15,000 Union soldiers held near Richmond and spread word of President Lincoln's Proclamation of Amnesty and Reconstruction, which allowed a pardon and restoration of property for Confederates willing to cease the rebellion.
Kilpatrick left the main Union army at Stevensburg, Virginia, on February 28 and crossed the Rappahannock River. On February 29, Kilpatrick split with the 21-year-old Dahlgren, one of the youngest colonels in the Union army. The weather turned bad as the detachments separated. Rain turned to sleet, and the riders had to battle icy branches and cold, inky blackness as night fell. Dahlgren rode west and picked up a guide, a black youth named Martin Robinson. Robinson professed to know of a crossing of the James River west of Richmond. When they arrived at the spot, there was no way across the swollen river. Dahlgren flew into a rage and ordered Robinson hanged.
On March 1, Dahlgren and 200 men were ambushed and the young colonel was killed. The Kilpatrick-Dahlgren raid was a failure for the Union. Some 340 men and 1,000 horses were lost, few Confederates paid attention to the copies of the amnesty proclamation that were left by the cavalry, and no Union prisoners were freed. The raid was the last fighting until General Ulysses S. Grant began his epic campaign in May.