The work of President Johnson demands for its proper understanding some consideration of the condition of the political parties at the close of the war, for politics had much to do with reconstruction. The Democratic party, divided and defeated in the election of 1860, lost its Southern members in 1861 by the secession and remained a minority party during the remainder of the war. It retained its organization, however, and in 1864 polled a large vote. Discredited by its policy of opposition to Lincoln's Administration, its ablest leaders joined the Republicans in support of the war. Until 1869 the party was poorly represented in Congress although, as soon as hostilities ended, the War Democrats showed a tendency to return to the old party. As to reconstruction, the party stood on the Crittenden-Johnson resolutions of 1861, though most Democrats were now willing to have slavery abolished.
The Republican party--frankly sectional and going into power on the single issue of opposition to the extension of slavery--was forced by the secession movement to take up the task of preserving the Union by war. Consequently, the party developed new principles, welcomed the aid of the War Democrats, and found it advisable to drop its name and with its allies to form the Union or National Union party. It was this National Union party which in 1864 nominated Abraham Lincoln, a Republican, and Andrew Johnson, a Democrat, on the same ticket. Lincoln's second Cabinet was composed of both Republicans and War Democrats. When the war ended, the conservative leaders were anxious to hold the Union party together in order to be in a better position to settle the problems of reconstruction, but the movement of the War Democrats back to their old party tended to leave in the Union party only its Republican members, with the radical leaders dominating.
In the South the pressure of war so united the people that party divisions disappeared for a time, but the causes of division continued to exist and two parties, at least, would have developed had the pressure been removed. Though all factions supported the war after it began, the former Whigs and Douglas Democrats, when it was over, liked to remember that they had been "Union" men in 1860 and expected to organize in opposition to the extreme Democrats, who were now charged with being responsible for the misfortunes of the South. They were in a position to affiliate with the National Union party of the North if proper inducements were offered, while the regular Democrats were ready to rejoin their old party. But the embittered feelings resulting from the murder of Lincoln and the rapid development of the struggle between President Johnson and Congress caused the radicals "to lump the old Union Democrats and Whigs together with the secessionists--and many were driven where they did not want to go, into temporary affiliation with the Democratic party." Thousands went very reluctantly; the old Whigs, indeed, were not firmly committed to the Democrats until radical reconstruction had actually begun. Still other "loyalists" in the South were prepared to join the Northern radicals in advocating the disfranchisement of Confederates and in opposing the granting of suffrage to the negroes.