Category: History
Question: During this battle, a bayonet charge by the 20th Maine, led by Joshua Chamberlain, helped defend one important hill. Besides Little Round Top, other areas of contest included Devil's Den and the Peach Orchard. The decisive action in this battle was a failed assault on Cemetery Ridge known as Pickett's Charge. For 10 points, name this Union victory after which Abraham Lincoln gave a namesake "address."
Answer: Battle of Gettysburg

The Battle of Gettysburg (locally  ) was a three-day battle in the American Civil War fought between Union and Confederate forces between July 1 and July 3, 1863, in and around Gettysburg, Pennsylvania. The battle, which was won by the Union, is widely considered the Civil War's turning point, ending the Confederacy's aspirations to establish an independent nation. It was the Civil War's bloodiest battle, claiming over 50,000 combined casualties over three days.
In the Battle of Gettysburg, Union Major General George Meade's Army of the Potomac defeated attacks by Confederate General Robert E. Lee's Army of Northern Virginia, halting Lee's invasion of the north and forcing his retreat.
After his success at Chancellorsville in Virginia in May 1863, Lee led his Confederate forces through Shenandoah Valley to begin the Gettysburg Campaign, his second attempted invasion of the north. With Lee's army in high spirits, he intended to shift the focus of the summer campaign from war-ravaged Northern Virginia in the hopes of penetrating as far as Harrisburg, Pennsylvania or Philadelphia, which he hoped would convince northern politicians to abandon their prosecution of the war. President Abraham Lincoln initially prodded Major General Joseph Hooker to move his Union forces in pursuit of Lee, but relieved Hooker of his command just three days before the battle, replacing him with Meade.
On July 1, 1863, as Lee's forces moved on Gettysburg in the hopes of destroying the Union Army, the two armies initially collided, and the battle commenced. Low ridges to the northwest of Gettysburg were initially defended by a Union cavalry division under Brigadier General John Buford, and soon reinforced with two corps of Union infantry. Two large Confederate corps assaulted them from the northwest and north, however, collapsing the hastily developed Union lines, leading them to retreat through the streets of Gettysburg to the hills just south of the city. On the second day of battle, on July 2, the Union line was laid out in a defensive formation resembling a fishhook. In the late afternoon, Lee launched a heavy assault on the Union's left flank, leading to fierce fighting at Little Round Top, the Wheatfield, Devil's Den, and the Peach Orchard. On the Union's right flank, Confederate demonstrations escalated into full-scale assaults on Culp's Hill and Cemetery Hill. Despite incurring significant losses, Union forces held their lines.
On the third day of battle, July 3, fighting resumed on Culp's Hill, and cavalry battles raged to the east and south of Gettysburg, but the main military engagement was a dramatic Confederate infantry assault of approximately 12,000 Confederates troops, who led attacked the center of the Union line at Cemetery Ridge in what is known as Pickett's Charge. The Confederate charge was repelled by Union rifle and artillery fire, leading to great Confederate losses. The following day, on the Fourth of July, Lee led his Confederate troops on the torturous retreat from the north. Between 46,000 and 51,000 soldiers from both armies were casualties in the three-day battle, representing the most deadly battle in U.S. history. 
On November 19, President Lincoln traveled to Gettysburg, where he spoke at a ceremony dedicating Gettysburg National Cemetery that honored the fallen Union soldiers and redefined the purpose of the Civil War in his famed Gettysburg Address, a 271-word address considered one of the famous speeches in American history.