In May 1863, after his army's exhilarating victory at the Battle of Chancellorsville, Confederate commander Robert E. Lee wanted to move fighting away from Virginia and invade Union territory once again. He had been repulsed earlier in Maryland, thwarted in his advance at the Battle of Antietam in September 1862.

With Union forces in shambles after their humbling loss at Chancellorsville, Lee seized his opportunity. He reorganized his forces at nearby Fredericksburg, Va., and seized the garrisons at Winchester, Va., and Martinsburg W. Va., in June 1863. From there the Confederates struck into Maryland and Pennsylvania. Once in Pennsylvania, the army of more than 70,000 men could take advantage of the bounty of the surrounding farm country and keep Union forces on the run.

Faced with a great sense of urgency, President Abraham Lincoln called upon Pennsylvania to provide volunteers to aid in the Union defense. Soldiers from New York also answered this call, as did New Jersey. By the end of June, Lincoln had also replaced his field commander, Gen. Joseph Hooker, with Gen. George R. Meade.

Lee's ultimate goal was to seize the city of Harrisburg, the industrial hub of central Pennsylvania. From that point, the Confederates would hold a decided advantage over the fumbling Union defenses. Yet Harrisburg would not be the site of a battle. Geography played a part in this happening. A dozen roads led into Gettysburg, Pa., from all over the area. To this day, the road names - Baltimore, Emmitsburg, Taneytown, Chambersburg, York, and Harrisburg - reflect the fact that Gettysburg laid as a central junction point in south-central Pennsylvania, just north of the Maryland border. One writer described it as "a town on the rise," with its 2,000 residents in July 1863. Gettysburg would heretofore be defined by this battle that would start on the month's first day.

On the morning of July 1, 1863, two Confederate brigades under the command of Maj. Gen. Henry Heth came from the west along the Chambersburg Pike, and encountered a cavalry brigade commanded by Brig. Gen. John Buford. Whether or not this meeting was due to Confederate soldiers "seeking shoes" is a matter for debate, yet this incident did ignite the Battle of Gettysburg.

The battle widened as the day went on. Union reinforcements turned back the Confederate infantry, and the Confederate Second Corps opened a massive three-pronged attack from the north in the afternoon. The energized Confederate force held the overall edge in their spirited infantry charges, yet the Union forces repositioned themselves at critical defensive junctures throughout this first day, including Cemetery Ridge and Culp's Hill. This movement would prove critical in determining what would take place on the following two days.

Notable in the fighting on July 1 was the contribution of state militias, forerunners of today's National Guard. One of the fiercest exchanges took place at McPherson's Farm just north of the center of Gettysburg, where the 2nd Mississippi Volunteer Infantry battle against the Union Army's "Iron Brigade," a unit comprised of five regiments from Wisconsin, Michigan and Indiana. These units were the 2nd, 6th, and 7th Wisconsin, the 19th Indiana, and the 24th Michigan.

The casualty total for the 2nd Wisconsin was especially high; however, the Union forces were able to procure key high positions outside Gettysburg at day's end. This positioning would prove fortuitous with regard to what would happen the next two days.

On the morning of July 1, 1863, two Confederate brigades under the command of Maj. Gen. Henry Heth came from the west along the Chambersburg Pike, and encountered a cavalry brigade commanded by Brig. Gen. John Buford. Whether or not this meeting was due to Confederate soldiers "seeking shoes" is a matter for debate, yet this incident did ignite the Battle of Gettysburg.

The battle widened as the day went on. Union reinforcements turned back the Confederate infantry, and the Confederate Second Corps opened a massive three-pronged attack from the north in the afternoon. The energized Confederate force held the overall edge in their spirited infantry charges, yet the Union forces repositioned themselves at critical defensive junctures throughout this first day, including Cemetery Ridge and Culp's Hill. This movement would prove critical in determining what would take place on the following two days.

Notable in the fighting on July 1 was the contribution of state militias, forerunners of today's National Guard. One of the fiercest exchanges took place at McPherson's Farm just north of the center of Gettysburg, where the 2nd Mississippi Volunteer Infantry battle against the Union Army's "Iron Brigade," a unit comprised of five regiments from Wisconsin, Michigan and Indiana. These units were the 2nd, 6th, and 7th Wisconsin, the 19th Indiana, and the 24th Michigan.

The casualty total for the 2nd Wisconsin was especially high; however, the Union forces were able to procure key high positions outside Gettysburg at day's end. This positioning would prove fortuitous with regard to what would happen the next two days.

By July 2, a total of 150,000 soldiers converged on the Gettysburg area. Cemetery Ridge was one of the defensive posts that the Union Army held by that morning, just to the west of the village. Reinforcements for the North also arrived to bolster the force's staggering fortunes. Meanwhile, Gen. Lee had planned to attack the left and right flanks of the Union lines in order to have their defenses collapse.

The story of the day, as seen through the states' militias in action, was coming to the aid of the larger forces on the battlefield. The first instance was the action at Cemetery Ridge. The Confederate infantry laid heavy siege on the lines of the Union III Corps. The First Minnesota Infantry, one of the first units called to service at the outset of the War, originally was placed in the middle of the defensive line. But when a large gap developed, over 250 Minnesotans attacked the Confederate advance at double time and bought time so that the III Corps could fend off the Southerners. But this defense happened at a astonishing cost. By day's end, over 80% of the men engaged in the Cemetery Ridge encounter failed to answer that night's roll call. The tenacity and sacrifice of the First Minnesota is remembered as one of the most important maneuvers of the Battle.

Another incident took place later in the afternoon on Little Round Top, a hill that afforded a tactical advantage for the side that could maintain their position. Little Round Top was left unprotected as two Alabama regiments started an attack in order to gain a higher foothold. If the Union Army lost their hold at this point, the Confederate advance could gain an advantage; the order came that the Union had to hold Little Round Top "at all costs."

It was then that Maine 20th's Maine Infantry Regiment entered a vanguard of legendary units in the American war annals. Led by Col. Joshua L. Chamberlain, a former professor at Maine's Bowdoin College, this unit once sagged in morale. After marching all day and night to reach Gettysburg, the regiment was ordered late in the afternoon of July 2 to occupy critical terrain between two hills, Big and Little Round Top.

The 20th Maine held off six attacks by the determined Alabama men. Chamberlain knew that his regiment was low on ammunition and could not withstand a seventh charge. He ordered a rotating counterattack with fixed bayonets, whereby the 20th scurried down the slopes of Little Round Top and broke the will of the Confederates. Thanks to the once-lightly regarded Maine regiment, the Union defense held. After a noticeable period of low morale, the heroic actions of the Minnesota and Maine regiments helped buoy the spirits of the Union forces.

Given the setbacks on July 2, the Confederate forces had to make a concerted effort in order to wrest control away from the North and turn the tide of battle. On this day, Lee decided to make a bold gamble through two different methods.

First, he decided to assault the federal line along Cemetery Ridge, where most of the fighting had centered on the second day of hostilities. This was accomplished through an artillery barrage designed to soften the North's resistance. Next, General Lee ordered Lt. Gen. James Longstreet to lead a massive infantry assault from Seminary Ridge. Over 12,000 Soldiers from 10 brigades, including Virginia regiments all under the command of Maj. Gen. George Pickett, advanced on the Union forces. However, the Union Soldiers were protected in great part by breastworks (stone barriers that were the height of a man's breast, around 4 feet high).

Pickett, who led five brigades in the fight, however, became the figure for whom the failed offensive was named. In the ensuing action, about 5,000 Confederates were killed or wounded. It failed, and it was during this sequence at which the "High Water Mark of the Confederacy" was reached, both on the battlefield and with regard to the Southern offensive into Northern territory.

It was in this series of actions that the South hoped to seize control of momentum in one master stroke. "Pickett's Charge" would characterize the near misses that Confederate forces experienced earlier; even with the enormous momentum that Lee's army moved forward, the tactical advantage of weapons, provisions, and manpower that the Union held stayed intact. General Meade placed Maj. Gen. Winfield Hancock in charge of three corps units on this day: the First, Second, and Third Corps. This consisted of over half the Union troops and made the difference in resisting the Confederate advance.

Afterward, General Lee ordered his Army of Northern Virginia to disengage, and turn south. With this Southern retreat and later reorganization, thus ended the Battle of Gettysburg. Meade would be sharply criticized for his failure to harass the withdrawing Confederates and to attempt to draw the American Civil War to an end at this critical juncture. The remainder of his military career became highly controversial because of what took place after the Battle of Gettysburg, and overshadowed the accomplishments that pivoted the Union forces into a state of rejuvenation.

In conjunction with the Battle of Vicksburg won the next day after a 65-day siege of the Mississippi town, the Union military reversed its previously checkered fortunes. Although many debate that the defeated Confederates should have been pursued back into Maryland and Virginia in an effort to wholly defeat them, simple exhaustion after three days of intense fighting allowed the conflict to continue.

But the victory marked a turning point in the fighting, as Robert E. Lee's once invincible aura had met its match with the ability of the Union army to hold firm at vital junctures. It ultimately led to the Confederate surrender in spring 1865.

The toll on the town was colossal. In the end, over 51,000 were killed in the battle. The stench of corpses of humans and animals lingered on until outside assistance could mitigate the foul conditions. Even though the Battle of Antietam fought nine months earlier had massive casualty totals, the cumulative damage wrought upon the Gettysburg area was staggering.

Later that year, the dedication of the Gettysburg National Cemetery memorialized the cost in human life. On November 19, 1863, President Abraham Lincoln traveled to the village to the cemetery opening. He would distinguish himself with brevity as had no other national leader. His two-minute speech put forth the declaration that the sacrifices of all the casualties would test the union of the United States, and calls upon the tenets of the original Declaration of Independence. It also hints at his later calls for reconciliation between the North and South. This short address came to be the words that the American people remembered, contrasted with the two-hour oratory that keynote speaker Edward Everett gave to the crowd. Historians point to it as one of the best-written speeches any American president has given.

Monuments at the Gettysburg National Battlefield, and on the headstones of the National Cemetery, commemorate the service and sacrifice of the state militias that fought for their respective armies on the three days of Gettysburg. To today's National Guard, Gettysburg is a touchstone to many present day units. There are presently 71 units from 23 states with lineage to their ancestral militia units who fought the pivotal battle. Pennsylvania has the most units still extant, with nine; Massachusetts, the second most, with seven. Among Southern states, Virginia and Georgia, retain seven and six units respectively. The notion of service to one's state and the nation is part of these Soldiers' oath, just as it was on those three extremely hot days in that now-tranquil Pennsylvania town in July 1863.

Wreath-laying ceremony hosted by the Pennsylvania National Guard at the Gettysburg 150th anniversary.