Which of the serious defeats for the Union came first in the American Civil War: the Battle of Chickamauga or the Battle of Fredericksburg?
Battle of Fredericksburg The Battle of Fredericksburg was fought December 11–15, 1862, in and around Fredericksburg, Virginia, between General Robert E. Lee's Confederate Army of Northern Virginia and the Union Army of the Potomac, commanded by Major General Ambrose Burnside, as part of the American Civil War. The Union Army's futile frontal attacks on December 13 against entrenched Confederate defenders on the heights behind the city are remembered as one of the most one-sided battles of the war, with Union casualties more than three times as heavy as those suffered by the Confederates. A visitor to the battlefield described the battle to U.S. President Abraham Lincoln as a "butchery."
Battle of Sailor's Creek The Battle of Sailor's Creek (also known in whole or in part as Sayler's Creek, Little Sailor's Creek, Harper's Farm, Marshall's Cross Roads, Hillsman Farm, Double Bridges, or Lockett's Farm) was fought on April 6, 1865, near Farmville, Virginia, as part of the Appomattox Campaign, near the end of the American Civil War. It was the largest battle of the Appomattox Campaign and the last major engagement between the Confederate Army of Northern Virginia and local Richmond area defense forces commanded by General Robert E. Lee and the Union Army (Army of the Shenandoah, Army of the Potomac and Army of the James) under the overall direction of Union General-in-Chief Lieutenant General Ulysses S. Grant before Lee's surrender of his army to Grant at Appomattox Court House three days later.