The situation that resulted in president Andrew johnsons impeachment was at its heart an issue surrounding

The main official reason was his violation of a tenure in office law which he was charged with breaking when he fired his Secretary of War, Edward Stanton. There were a lot of people in Congress that wanted him out of office and were looking for some reason to get him out. He was unpopular because, like Lincoln, he did not want to punish the defeated southern states, but rather to take them back into the union as seamlessly as possible. He was a converted Democrat and from a slave state, Tennessee, and so had no natural power base to work in his favor. President Johnson was primarily impeached for 1) violating the 1867 Tenure of Office Act. Other charges included 2) violating the Command of the Army Act and 3) libeling Congress with "inflammatory and scandalous harangues."