— A Confederate army invading the North under Gen. Robert E. Lee and the Union Army of the Potomac led by Maj. Gen. George G. Meade collided over three blazing summer days at Gettysburg, Pa., 150 years ago this week in the Civil War. The July 1-3 battle on Pennsylvania farmland would mark the turning point of the war as the Union claimed its biggest victory, repulsing Lee’s second incursion into the North. Gettysburg also would be the bloodiest battle with some 51,000 casualties and give rise to Lincoln’s timeless “Gettysburg Address.” The battle began July 1, 1863, when Lee massed his Army of Northern Virginia at a crossroads at Gettysburg, driving Union defenders back to Cemetery Hill. More troops arrived overnight for both sides and vicious fighting resumed the next day. The fierce combat raged over fields, a sunken road and on hilltops until nightfall. Through it all, the Union desperately held its positions, and then on July 3, momentum turned against Lee. Confederate infantrymen were flung backward. But a major Confederate assault, Pickett’s charge, briefly punctured the Union line until frenzied federal fighters forced back the charge and the Union line held. By July 4, 1863, a defeated Lee began withdrawing southward toward Virginia, his bloodied and exhausted column strung out for miles. Lee’s defeat at Gettysburg marked a turn for the worse for a Confederacy whose end would come ultimately in 1865. That July 4, 1863, also brought another Union victory: Confederate forces weathering a long siege at Vicksburg, Miss., capitulated to federal forces now in full control of the Mississippi River.