Although fighting with improvised armies, the field commanders of the Civil War often recognized the value of fortifications. At Big Bethel, First Manassas, and Ball's Bluff, field fortifications were used in peripheral ways that often had little impact on the outcome of the battles, yet field armies dug in deeper and more widely after each engagement. The capital cities of the opposing sides were ringed with the beginnings of massive earthworks designed to protect the political and administrative centers of the Union and Confederate war efforts. Even along the Atlantic seacoast, fortifications came to play a role in combined operations designed to close blockade-running ports and open the door to future Union incursions on the edges of Confederate soil.
One of the first battles of the war occurred near Big Bethel, a rural church on the Yorktown Peninsula. The Federals had retained control of Fortress Monroe on the tip of the Peninsula after Virginia seceded from the Union on April 17. Monroe was one of three forts in the seceded states still under Union control. It was strategically located to serve as a jumping-off place for an advance up the Peninsula to Richmond. Such an attempt would be made by McClellan the following spring. In May 1861, Maj. Gen. Benjamin F. Butler occupied the post with a small garrison and easily controlled Hampton and Newport News as well.
The Confederates shifted troops to Yorktown, halfway up the Peninsula and the site of the American victory that had brought the Revolution to a close in 1781. Col. Daniel Harvey Hill's 1st North Carolina (six months) reached Yorktown on May 25 and began to dig in. "We worked all night throwing up fortifications," Hill wrote his wife, and "are now in a very strong position and I have not the slightest uneasiness." His men dug along the most advantageous ground outside town, which happened to be the same spot where Lord Cornwallis had planted his own works eighty years earlier. The British earthworks that protected the town were reworked and incorporated into Hill's new line. The diggers uncovered "human bones, powder, car-