In 1864, a group of concerned citizens established the Gettysburg Battlefield Memorial Association (GBMA) whose purpose was to preserve portions of the battlefield as a memorial to the Union Army that fought here. The GBMA transferred their land holdings to the Federal government in 1895, which designated Gettysburg as a National Military Park. A Federally-appointed commission of Civil War veterans oversaw the park's development as a memorial to both armies by identifying and marking the lines of battle. Administration of the park was transferred to the Department of the Interior, National Park Service in 1933, which continues in its mission to protect, preserve and interpret the Battle of Gettysburg and the Gettysburg.
Fought over the first three days of July 1863, the Battle of Gettysburg was one of the most crucial battles of the Civil War. The fate of the nation literally hung in the balance that summer of 1863 when General Robert E. Lee, commanding the "Army of Northern Virginia", led his army north into Maryland and Pennsylvania, bringing the war directly into northern territory. The Union "Army of the Potomac", commanded by Major General George Gordon Meade, met the Confederate invasion near the Pennsylvania crossroads town of Gettysburg,and what began as a chance encounter quickly turned into a desperate, ferocious battle. Despite initial Confederate successes, the battle turned against Lee on July 3rd, and with few options remaining, he ordered his army to return to Virginia. The Union victory at the Battle of Gettysburg, sometimes referred to as the "High Water Mark of the Rebellion" resulted not only in Lee's retreat to Virginia, but an end to the hopes of the Confederate States of America for independence.
The Gettysburg National Military Park archival and museum collection contains an extensive array of objects and documents on the Battle of Gettysburg, its aftermath, its commemoration, and other parts of the American Civil War. The collection also holds the Gettysburg Cyclorama Painting, the largest and most complete painting of the battle existing. Historic furnishings are housed and exhibited in the David Wills House (where Lincoln completed the Gettysburg Address), the Brian farmhouse, and the Leister farmhouse. The park's extensive archival collections document the establishment and management of the national military park as a commemorative landscape beginning in 1864.