The Republican party was compelled to disguise itself as "Union" in 1864, and it paid for the disguise during the next four years. Upon the death of Lincoln, the Tennessee Democrat, Andrew Johnson, took the oath of office. The bond which kept Democrats and Republicans together as Unionists had dissolved with the surrender of Lee, so that Johnson was enabled to follow his natural bent as a strict constructionist. His policies had carried him far away from the radical Republicans before Congress convened for its session of 1865-66, and led to a positive breach with that body in 1866. The quarrel between Johnson and the Republican leaders was occasioned by his views upon the rights of the Southern States, conquered in war and held within the military grasp of the United States. It was his belief, as it had been Lincoln's, that these States were still States and were in the Union, even though in a temporarily deranged condition. As President, entrusted with force to be used in executing the laws, he regarded himself as sole judge of the time when force should no longer be needed. And in this spirit he offered pardon to many leaders of the Confederacy in May, 1865. He followed amnesty with provisional governments, and proclaimed rules according to which the conquered States should revise their constitutions and reestablish orderly and loyal governments. He had reorganized the last of the eleven States before Congress could interfere with him. The difference between Johnson and his Republican associates lay in the character of the restored electorates in the South. The whole white population had, in most States, been implicated in secession. There was no Union faction in the South that remained loyal throughout the war. Pardoned and restored to a full share in the Government, these Southern leaders would come back into Congress as Democrats, and with increased strength. The Thirteenth Amendment abolished slavery, and raised the representation of the negroes in the South from the old three-fifths ratio to par. Every State would come back with more Representatives than it had had before the war, and with the aid of Northern Democrats it was not unlikely that a control of Congress might be obtained. To Northern Republicans it was unreasonable that the conquered South should be rewarded instead of punished, and that any theory of reconstruction should risk bringing into power the party that Union men, headed by Lincoln, had defeated in 1864. Politicians, interested in the spoils of office, were enraged at the thought of losing them. Disinterested Northerners, who had sacrificed much to save the Union, believed it unsafe at once to hand it over to a combination of peace Democrats and former "rebels." Yet this was Johnson's plan, and Congress, with radical Republicans in control, set about to prevent it.