Lewis Thornton Powell was an American Confederate soldier who attempted to assassinate William Henry Seward as part of the Lincoln assassination plot. Wounded at the Battle of Gettysburg, he later served in Mosby's Rangers before working with the Confederate Secret Service in Maryland. John Wilkes Booth recruited him into a plot to kidnap Lincoln and turn the president over to the Confederacy, but then decided to assassinate Lincoln, Seward, and Vice President Andrew Johnson instead, and assigned Powell the task to kill Seward.

John Harrison Surratt Jr. was an American Confederate spy who was accused of plotting with John Wilkes Booth to kidnap U.S. President Abraham Lincoln; he was also suspected of involvement in the Abraham Lincoln assassination. His mother, Mary Surratt, was convicted of conspiracy by a military tribunal and hanged; she owned the boarding house that the conspirators used as a safe house and to plot the scheme.