As the war drew to a close in April 1865 , Greeley and the '' Tribune '' urged magnanimity towards the defeated Confederates , arguing that making martyrs of Confederate leaders would only inspire future rebels . This talk of moderation ceased when Lincoln was assassinated by John Wilkes Booth . Many concluded that Lincoln had fallen as the result of a final rebel plot , and the new president , Andrew Johnson , offered $ 100,000 for the capture of fugitive Confederate president Jefferson Davis . After the rebel leader was caught , Greeley initially advocated that " punishment be meted out in accord with a just verdict "
Lincoln was assassinated
Assassination of Abraham Lincoln
Horace Greeley