In December 1860, more than four years before John Wilkes Booth assassinated Abraham Lincoln in Ford's Theater in Washington, the actor wrote a 21-page manuscript that showed his fanatical state of mind, his sympathies for the Southern secessionists, and his association with the historical characters he portrayed in Shakespeare's plays.
In the view of Lincoln scholars, had these sentiments been known to the officials responsible for guarding the president, it is possible that Booth would not have had such easy access to the theater on April 14, 1865.
The manuscript, written in Philadelphia, was intended as a speech, but it was never delivered. Nor has it ever been published.
It was discovered last year in the theatrical archives of the private Players Club at 16 Gramercy Park South in Manhattan, the former home of Edwin Booth, the assassin's older brother, who was a better-known actor at the time.
"I think the JWB manuscript is a fascinating document," said David Herbert Donald, a Harvard historian. "The 'speech' is revealing both of Booth's views on the secession crisis and of his disorderly, incoherent state of mind in this time of great emotional turmoil."
An undated note appended to the manuscript, written by Edwin Booth, reads: "This was found [long after his death] among some old play-books and clothes left by JWB in my house."
After sorting through the contents of his brother's trunk some time in the 1870s, Edwin Booth burned the costumes and clothes, but he saved the manuscript.
The manuscript, which is now being made accessible to scholars for the first time, was found by Robert Giroux, the editor and publisher at Farrar, Straus & Giroux, while he was combing through old documents at the Players Club.
"I had a bit of a shock when I realized that the initials JWB stood for John Wilkes Booth," Mr. Giroux said as he sat behind Edwin Booth's desk in a study overlooking Gramercy Park. "Even though he was a rabid sympathizer with the secessionists, he believed he was defending the Union."
The manuscript is scrawled in heavy black ink, in rather erratic handwriting, with crossed-out
words, misspellings and errors of grammar. It was written in the house of his sister, Asia Booth Clarke, in Philadelphia, where Booth and his mother were spending the Christmas holidays.
In the rambling manuscript, Booth calls himself "a Northern man" who intends to "fight with all my heart and soul -- even if there's not a man to back me" -- for equal rights and justice for the South as well as the North.
Referring to the secession of South Carolina, he says that "she is fighting in a just cause with God Himself upon their side." But he adds, "I don't believe that any of us are represented truly in Washington" because the men there are "Abolitionists."
Booth blames the cause of disunion on "nothing but the constant agitation of the slavery question."
The South, he says, has "a right, according to the Constitution," to keep and hold slaves. Furthermore, the institution of slavery brings "happiness for them."
True, he concedes, "I have seen the black man whipped, but only when he deserved more than he received."
Attacking the "free press," he writes, "Is it not [what Shakespeare says of the drama] to hold as it were the mirror up to nature?" He accuses newspapers of telling "a hundred lies calculated to lead mankind into folly and into vice."
Somehow twisting the words of Iago in "Othello" to fit his own views on states' rights, he writes: "But he who steals my purse steals trash. It does more than that. It filches from me my good name. It induces my very servant to poison me at my meals, to murder me in my sleep."
In the most personal sentence in the manuscript, Booth says, "I saw John Brown hung and I may say that I helped to hang John Brown."
Mr. Giroux notes that, according to Booth's sister, Asia, the actor had briefly joined the Richmond Greys, a unit of the Virginia state militia, which helped to pursue and capture the revolutionary abolitionist after the insurrection and killings at Harpers Ferry in 1859.
At no point in the manuscript does Booth mention the president-elect's name.
Mr. Giroux says Booth began to write feverishly just after South Carolina seceded on Dec. 20, 1860.
Why did Edwin Booth preserve the fiery "JWB" manuscript? Mr. Giroux, who is president of the club's library, and Raymond Wemmlinger, the club's curator and librarian, believe that he recognized its future historical significance.
"Perhaps he thought the manuscript might help posterity to understand his brother's tragedy better," Mr. Giroux said.
Edwin Booth's immediate reaction to the assassination and the death of his brother can also be found in the Players archives. It is the draft of an open letter addressed "To the People of the United States" on April 20, 1865.