Of the cast which Abraham Lincoln’s assassin had so hopefully assembled in Washington for the roles he had assigned in the crime, five of them, including himself, were now dead on July 9. Booth, the star-tragedian of the historic melodrama, lay buried in secret under the floor in the southwestern end of the Arsenal penitentiary building. Secretary of War Edwin Stanton was afraid that Booth’s body would be made into a martyred symbol by ex-Confederates, and so it was likely that not ten people in the United States knew where the assassin, killed on April 26, was buried. A lavish display under cover of night after the assassin’s death was made to fool the public into thinking that the assassin’s body had been buried well off-shore in the Anacostia River near the Washington Navy Yard. Mrs. Mary Surratt, Lewis Powell, George Atzerodt, and David Herold, hanged on July 7, slept in the row of four graves outside the prison wall at the penitentiary.
The remaining four guilty prisoners were still inside the prison walls. Dr. Samuel Mudd, Edman Spangler, Michael O’Laughlen, and Samuel Arnold knew they were found guilty as charged, but by July 10, they still had not been told of their sentences nor what had happened to the executed; today this might be termed as cruel and unusual punishment. Not so in 1865. They had been told they were found guilty by the military commission, but that was all. What the sentences were and where they would be served rested with President Andrew Johnson. Considering their cases in the days following the execution in the prison yard, the president decided that the remaining four would serve their terms at hard labor in the penitentiary at Albany, N.Y. Sec. of War Stanton was advised that the prisoners would be told of their sentences on July 17, but on July 15, two days before the appointed time of departure, the President changed his mind, and decided that the four prisoners would serve their sentences at Fort Jefferson instead. Ft. Jefferson was the cruelest of the government’s prisons; it was situated on the Dry Tortugas, one of several arid, sun-cooked islands located some one hundred miles to the southwest off the mainland of Florida. No government guards wanted to serve there, where access was limited to ships, and they considered this tour of duty the same as being under a prison sentence.
What caused this sudden switch in the President’s plans is not a matter of record. It may have been an influence by Sec. Stanton. He was known to regard the four remaining prisoners as representatives of what he termed “the treacherous South”. He had worked hard to prevent the expected rescue of Booth’s body and of the persons of the four who had been hanged. It seemed evident that the War Department feared that vengeful friends of the condemned men would stage a sudden jail-delivery in their behalf, either in Washington or in Albany, or enroute to Albany.
In Washington on July 13, President Johnson appointed William Marvin the provisional governor of Florida. In the deep South, as the week closed, former Confederate Maj. Gen. Joseph “Jo” Shelby led a force of some 1,000 former unsurrendered Confederate soldiers across the border into Mexico, on their way to Mexico City, to offer their services as a “foreign legion” to Emperor Maximilian, ruler of Mexico.