In June 1864, Union Lieutenant General Ulysses S. Grant was intent on destroying Confederate General Robert E. Lee's army at Petersburg, Virginia. Lee saw an opportunity to capture undefended Washington, D.C., and sent Lieutenant General Jubal A. Early with 15,000 troops to invade the North. Moving through the Shenandoah Valley to Frederick, Maryland, Early expected only minor resistance but instead met an opposing force of 6,000 troops. Although his army prevailed at the Battle of Monocacy on July 9, 1864, the delay cost him his chance to take Washington and perhaps to turn the war in favor of the Confederacy. Early had departed Richmond on June 13, secured the Shenandoah Valley, and moved into Maryland, then after Monocacy advanced on Washington's defenses and reached Fort Stevens on July 11, but on July 12 found the odds too great and retreated into Virginia. At Monocacy Junction, a mix of veteran troops and untested 100-day men took cover in the railroad cut and offered fierce defense of the junction; stranded after Union soldiers burned the river bridge, they fought until late in the day and escaped over the railroad bridge. Best Farm was caught in artillery crossfire at the battle's beginning, Confederates found a way to ford the Monocacy River at Worthington Farm and shifted the battle to a new front, civilians hid in Thomas House during furious fighting there, Gambrill Mill became a field hospital for Union soldiers, and defending Monocacy Junction was key to the Union strategy.
