After opposing Congress Andrew Johnson becameThe first president to face what proceedings?

After opposing Congress, Andrew Johnson became the first president to face impeachment proceedings. In 1868, he was impeached by the House of Representatives primarily for violating the Tenure of Office Act by attempting to remove Edwin M. Stanton, the Secretary of War, from his position. Johnson was acquitted by the Senate and remained in office, but the impeachment highlighted the significant tensions between the presidency and Congress during Reconstruction.