General Robert E. Lee decided to take the war into the North in June 1863, allowing Southern farmers an uninterrupted growing season, and perhaps convincing European powers to aid the Confederacy. As the rebels invaded Pennsylvania, Harrisburg made a tempting target as a key transportation hub that promised access to a large cache of military supplies at nearby Camp Curtin. Its loss, as an important Union state capital, would be a major blow to Northern morale.
Union Major General Darius Couch was charged with the defense of Harrisburg. Low on troops, Couch did the best he could, hastily building fortifications on the heights directly across the Susquehanna River from Harrisburg. Pennsylvania and New York militia troops manned the defenses.
Confederate cavalry under Brigadier General Albert Jenkins captured nearby Mechanicsburg on June 28. The next day, his troops skirmished with Federals at Oyster Point (in present-day Camp Hill).
On June 30, Couch's troops met the Confederates at Sporting Hill, about five miles from Harrisburg. Throughout the afternoon, Union and Confederate forces fought the northernmost engagement of the Gettysburg campaign. Jenkins withdrew that day to join Lee's army concentrating near Gettysburg. Harrisburg had been saved.