When the first inklings emerged early in 1861 that a fighting war pitting North versus South would soon break out, the residents of Washington, D.C.—at least those whose sympathies were with the Union—began to feel more than a little threatened. Though it was a haven for freed blacks, the District of Columbia also was the home of slave-owning whites and had the ambience of a Southern city, sitting below the Mason-Dixon line and surrounded by the slave-owning states of Maryland and Virginia.

Subscribe Today

• Did you enjoy our article?
• Read more in America's Civil War magazine
• Subscribe online and save nearly 40%!!!
 

The city’s only defensive fortification was Fort Washington, built in 1809 well south of the city on the Maryland side of the Potomac River. Worse, only a handful of friendly troops were stationed nearby, and many of them defected to the Confederate side. By springtime,

Confederate flags flying in Northern Virginia could be seen across the Potomac from the city’s higher elevations.

In short, the Union capital was ripe for an invasion by the Confederates, and it wasn’t long before official Washington took notice.

In February, Maj. Gen. Winfield Scott, the Union Army commander, ordered Army Regulars into the city. By the end of April, some 11,000 Union troops had arrived to protect Washington. They set up makeshift camps in nearly every available space, including the Treasury Building, the Patent Office, City Hall, the Navy Yard and even inside the Capitol building.

Many of those troops were put to work in late May building a series of forts and interconnected rifle pits and trenches. An impetus for accelerating the work on this network of defensive forts came late in July, following the unexpected and disastrous Union defeat at the First Battle of Bull Run in Virginia. That shocking loss, just 30 miles southwest of Washington, raised new fears in the capital about an impending Confederate invasion.

The defeat at Bull Run “left no longer room to doubt” the need for “a chain of fortifications” around Washington, reflected General John Gross Barnard, who was soon appointed the Army of the Potomac’s chief engineer. “With our army too demoralized and too weak in numbers to act effectually in the open field against the invading enemy, nothing but the protection of defensive works could give any degree of security.”

The man chosen to oversee the building of the defensive works was Maj. Gen. George B. McClellan—West Point Class of 1846, Mexican War hero and the former chief engineer of the Illinois Central Railroad. McClellan took over as commander of the Army of the Potomac on July 27, just after First Bull Run. He immediately stepped up the fort and fortification-building effort. McClellan gave the job of overseeing construction to Barnard, who had fought at Bull Run.

“The chaos of Washington inspired McClellan to an almost frenzied activity,” Margaret Leech wrote in Reveille In Washington, her 1942 Pulitzer Prize–winning portrait of the city during the Civil War. “Convinced that the city was about to be attacked by an overwhelming force, he spent twelve and fourteen hours a day on horseback, and worked at his desk until early morning.”

While the 34-year-old general worked feverishly to process the thousands of volunteers for the Union Army, Barnard took over day-to-day supervision of construction of the forts. It continued at a frantic pace all summer.

The Massachusetts-born Barnard, West Point Class of 1833, had specialized in building garrisons and fortifications during his 28-year Army career. Among other things, he had helped build defenses in New York City, New Orleans and Pensacola, as well as in Tampico, Mexico, during the Mexican War in 1846. The effort in Washington first involved confiscating the land for the forts and their extensive fields of fire (as far, in some cases, as two miles), and then tearing down buildings and clearing large swaths of forests and farmland—without compensating property owners. “On both sides of the river, the farmers were ruined,” Leech noted. “Not only were their orchards and vegetable gardens trampled and their fields filled with tents, but the very face of the land was changed, as its soil was shifted into high mounds and deep ditches.”

Help HistoryNet by bookmarking to