Winfield Scott Hancock

Winfield Scott Hancock (February 14, 1824 – February 9, 1886) was a United States Army officer and the Democratic nominee for President of the United States in 1880. He served with distinction in the Army for four decades, including service in the Mexican–American War and as a Union general in the American Civil War. Known to his Army colleagues as "Hancock the Superb," he was noted in particular for his personal leadership at the Battle of Gettysburg in 1863. His military service continued after the Civil War, as Hancock participated in the military Reconstruction of the South and the Army's presence at the Western frontier.
Hancock's reputation as a war hero at Gettysburg, combined with his status as a Unionist and supporter of states' rights, made him a potential presidential candidate. When the Democrats nominated him for President in 1880, he ran a strong campaign, but was narrowly defeated by Republican James A. Garfield. Hancock's last public service involved the oversight of President Ulysses S. Grant's funeral procession in 1885.
Hancock's most famous service was as a new corps commander at the Battle of Gettysburg, July 1 to 3, 1863. After his friend, Maj. Gen. John F. Reynolds, was killed early on July 1, Maj. Gen. George G. Meade, the new commander of the Army of the Potomac, sent Hancock ahead to take command of the units on the field and assess the situation. Hancock thus was in temporary command of the "left wing" of the army, consisting of the I, II, III, and XI Corps. This demonstrated Meade's high confidence in him, because Hancock was not the most senior Union officer at Gettysburg at the time. Hancock and the more senior XI Corps commander, Maj. Gen. Oliver O. Howard, argued briefly about this command arrangement, but Hancock prevailed and he organized the Union defenses
At the close of the war, Hancock was assigned to supervise the execution of the Lincoln assassination conspirators. Lincoln had been assassinated on April 14, 1865, and by May 9 of that year, a military commission had been convened to try the accused. The actual assassin, John Wilkes Booth, was already dead, but the trial of his co-conspirators proceeded quickly, resulting in convictions. President Andrew Johnson ordered the executions to be carried out on July 7. Although he was reluctant to execute some of the less-culpable conspirators, especially Mary Surratt, Hancock carried out his orders, later writing that "every soldier was bound to act as I did under similar circumstances."
https://en.wikipedia.org/wiki/Winfield_Scott_Hancock