I do not believe a more conscientious man ever lived.

His judgments were sometimes peculiar, but they were upright and sincere, having reasons, which he could give with power and effect, behind them.

Yet was he a born politician, crafty to a degree, and always successful, relying upon a popular following which never failed him.
In 1860 he supported the quasi-secession Breckenridge and Lane Presidential ticket, but in 1861 he stood true to the Union, retaining his seat in the Senate until he was appointed military governor of Tennessee.

Nominated for Vice President on the ticket with Lincoln, in 1864, he was elected, and upon the assassination of Lincoln succeeded to the Presidency.

Having served out his term as President he returned to Tennessee to engage in the hottest kind of politics, and though at the outset defeated finally regained his seat in the Senate of the United States.
He hated Grant with a holy hate.