text: He also closely watched the handling of the Trent Affair in late 1861 to make sure there was no escalation into a war with Britain.Seward's main role was to keep Britain and France from supporting the Confederacy.He was successful after indicating to Britain and France that the Union would declare war on them if they supported the South.Assassination John Wilkes Booth was a well-known actor and a Confederate spy from Maryland; though he never joined the Confederate army, he had contacts with the Confederate secret service.After attending Lincoln's last public address, on April 11, 1865, in which Lincoln stated his preference that the franchise be conferred on some black men, specifically "on the very intelligent, and on those who serve our cause as soldiers", Booth hatched a plot to assassinate the President.When Booth learned of the Lincolns' intent to attend a play with General Grant, he planned to assassinate Lincoln and Grant at Ford's Theatre.Lincoln and his wife attended the play Our American Cousin on the evening of April 14, just five days after the Union victory at the Battle of Appomattox Courthouse.At the last minute, Grant decided to go to New Jersey to visit his children instead of attending the play.On April 14, 1865, hours before he was assassinated, Lincoln signed legislation establishing the United States Secret Service, and, at 10:15 in the evening, Booth entered the back of Lincoln's theater box, crept up from behind, and fired at the back of Lincoln's head, mortally wounding him.Lincoln's guest, Major Henry Rathbone, momentarily grappled with Booth, but Booth stabbed him and escaped.After being attended by Doctor Charles Leale and two other doctors, Lincoln was taken across the street to Petersen House.After remaining in a coma for eight hours, Lincoln died at 7:22 in the morning on April 15.Stanton saluted and said, "Now he belongs to the ages.