On July 31, 1861, Capt. Daniel Leasure and 300 men of the 12th Pennsylvania Infantry halted at Bel Air's courthouse square after the First Battle of Bull Run, as Union forces moved to hunt Confederate sympathizers and confiscate weapons from local militia units in a county where many residents held Southern sympathies. After a brief stop at the courthouse, the troops blocked the roads leading out of Bel Air and rounded up local citizens, including Capt. Archer Jarrett of the Harford Light Dragoon, former state senator Henry Farandis, and merchant Thomas Hays. Jarrett was arrested but refused to reveal the location of his militia's weapons. Leasure's men searched the homes of Farandis and Hays but found no arms. Hays was also arrested, and both he and Jarrett were released later that year. After the unsuccessful search, the Pennsylvanians departed. Some Harford County residents later enlisted in the Confederate army, most notably Gen. James Archer, who was captured on July 1, 1863, at Gettysburg. Harford County resident Sgt. Alfred Hilton served in the 4th U.S. Colored Troops and carried his regiment's banner during the Battle of New Market Heights, Virginia, on September 29, 1864. After being shot through the leg, he called out, "Boys, save the colors!" He died a month later from his wounds and on April 6, 1865, was posthumously issued the Medal of Honor for his bravery.