Edward Porter Alexander - Civil War Service

Civil War Service

After learning of the secession of his home state of Georgia, Alexander resigned his U.S. Army commission on May 1, 1861, to join the Confederate Army as a captain of engineers. While organizing and training new recruits to form a Confederate signal service, he was ordered to report to Brig. Gen. P.G.T. Beauregard at Manassas Junction, Virginia. He became the Chief Engineer and Signal Officer of the Army of the Potomac on June 3.

At the First Battle of Bull Run, Alexander made history by being the first to use signal flags to transmit a message during combat over a long distance. Stationed atop "Signal Hill", in Manassas, Capt. Alexander saw Union troop movements and signaled to the brigade under Col. Nathan "Shanks" Evans, "Look out for your left, your position is turned", which meant that they were in danger of being attacked on their left flank. Upon receiving a similar message, Gens. Beauregard and Joseph E. Johnston sent timely reinforcements that turned the tide of battle in the Confederates' favor.

Alexander was promoted to major on July 1 and lieutenant colonel on December 31, 1861. During much of this period he was chief of ordnance, under Johnston's command, in what later became the Army of Northern Virginia. He was also active in signal work and intelligence gathering, dealing extensively with spies operating around Washington, D.C.

During the early days of the Peninsula Campaign of 1862, Alexander continued as chief of ordnance under Johnston, but he also participated in the combat at the Battle of Williamsburg, under Maj. Gen. James Longstreet. When Gen. Robert E. Lee assumed command of the army, Alexander was in charge of pre-positioned ordnance for Lee's offensive in the Seven Days Battles. Col. Alexander continued his intelligence gathering by volunteering to go up in a hot air balloon at Gaines' Mill on June 27, ascending several times and returning with valuable intelligence regarding the position of the Union Army.

Alexander continued in charge of ordnance for the Northern Virginia Campaign (Second Bull Run) and the Maryland Campaign (Antietam). He barely missed capture by Federal cavalry, under Col. Benjamin F. "Grimes" Davis, that had escaped from Harpers Ferry during the Maryland Campaign; over 40 of Longstreet's 80 ammunition wagons were captured.

Porter Alexander is best known as an artilleryman who played a prominent role in many of the important battles of the war. He served in different artillery capacities for Longstreet's First Corps of the Army of Northern Virginia, starting that role on November 7, 1862, after leaving Lee's staff to command the battalion that was the corps' artillery reserve. He was promoted to colonel on December 5. He was instrumental in arranging the artillery in defense of Marye's Heights at the Battle of Fredericksburg in December 1862, which proved to be the decisive factor in the Confederate victory. While the rest of Longstreet's corps was located around Suffolk, Virginia, Alexander accompanied Stonewall Jackson on his flanking march at the Battle of Chancellorsville in May 1863, and his artillery placements in Hazel Grove at Chancellorsville proved decisive.