His military career ended at the Battle of Gettysburg in July 1863, after he moved his III Corps without orders to an untenable position, where they suffered 40% casualties but slowed General James Longstreet's flanking maneuver.

[3] Sickles devoted considerable effort to trying to gain credit for helping achieve the Union victory at Gettysburg, writing articles and testifying before Congress in a manner that denigrated the intentions and actions of his superior officer, Maj. Gen. George Meade.

", roared Associate Defense Attorney John Graham, in a speech so packed with quotations from Othello, Judaic history and Roman law that it lasted two days and later appeared as a book.

Sickles surrendered at Attorney General Jeremiah Black's house, a few blocks away on Franklin Square, and confessed to the murder.

He secured several leading politicians as defense attorneys, among them Edwin Stanton, later to become Secretary of War, and Chief Counsel James T. Brady who, like Sickles, was associated with Tammany Hall.

"[15] Sickles had obtained a graphic confession from Teresa; it was ruled inadmissible in court, but was leaked by him to the press and printed in the newspapers in full.

The defense strategy ensured that the trial was the main topic of conversations in Washington for weeks, and the extensive coverage of national papers was sympathetic to Sickles.

[20] At the outbreak of the Civil War, Sickles worked to repair his public image by raising volunteer units in New York for the Union Army.

He lobbied his Washington political contacts and reclaimed both his rank and his command on May 24, 1862, in time to rejoin the Army in the Peninsula Campaign.

He was absent for the Second Battle of Bull Run,[10] having used his political influences to obtain leave to go to New York City to recruit new troops.

He also missed the Battle of Antietam because the III Corps, to which he was assigned as a division commander, was stationed on the lower Potomac, protecting the capital.

On January 16, 1863, President Abraham Lincoln nominated Sickles for promotion to the grade of major general to rank from November 29, 1862.

Sickles thought the Confederates were retreating, but these turned out to be elements of Stonewall Jackson's corps, stealthily marching around the Union flank.

[24] Concerned over his position and uncertain of Meade's exact intentions, a little after 2 p.m. he began to march his corps out to the Peach Orchard, almost a mile in front of Cemetery Ridge.

[25] This had two effects: it greatly diluted the concentrated defensive posture of his corps by stretching it too thin, and it created a salient that could be bombarded and attacked from multiple sides.

[26] Meade refused Sickles' offer to withdraw because he realized it was too late[27] and the Confederates would soon attack, putting a retreating force in even greater peril.

Gettysburg campaign historian Edwin B. Coddington assigns "much of the blame for the near disaster" in the center of the Union line to Sickles.

[28] Stephen W. Sears wrote that "Dan Sickles, in not obeying Meade's explicit orders, risked both his Third Corps and the army's defensive plan on July 2.

"[29] However, Sickles' maneuver has recently been credited by John Keegan with blunting the whole Confederate offensive that was intended to cause the collapse of the Union line.

As Sickles was carried by stretcher to the III Corps hospital on the Taneytown Road, he attempted to raise his soldiers' spirits by grinning and puffing on a cigar along the way.

He brought some of the first news of the great Union victory, and started a public relations campaign to defend his behavior in the conflict.

He preserved the bones from his leg and donated them to the museum in a small coffin-shaped box, along with a visiting card marked, "With the compliments of Major General D.E.S."

In anonymous newspaper articles and in testimony before a congressional committee, Sickles falsely maintained that Meade had secretly planned to retreat from Gettysburg on the first day.

The official citation accompanying his medal recorded that Sickles "displayed most conspicuous gallantry on the field, vigorously contesting the advance of the enemy and continuing to encourage his troops after being himself severely wounded.

"[37] Despite his one-legged disability, Sickles remained in the army until the end of the war and was disgusted that Lt. Gen. Ulysses S. Grant would not allow him to return to a combat command.

[6] Sickles served as U.S. Minister to Spain from 1869 to 1874, after the Senate failed to confirm Henry Shelton Sanford to the post, and took part in the negotiations growing out of the Virginius Affair.

"[39] Sickles maintained his reputation as a ladies' man in the Spanish royal court and was rumored to have had an affair with the deposed Queen Isabella II.

He served the commission zealously for most of the rest of his life in securing appropriations for monuments to New York regiments, batteries, and commanders and having them placed correctly on the Gettysburg battlefield.

This fencing came directly from Lafayette Square in Washington, D.C.[48] In fact, the park's borders were defined from its establishment until 1974 by a map prepared by Sickles.