Andrew Johnson was America’s 17th president, from 1865-1869 (not to be confused with Andrew Jackson, who was president 35 years earlier). He was the Vice President under Abraham Lincoln and became president upon Lincoln’s assassination. Even though he was from a southern state that seceded from the Union, he remained loyal to the U.S. He was impeached over his insistence in firing his Secretary of War in defiance of the Tenure of Office Act (but acquitted in the Senate by one vote), and subsequently failed to win presidential nomination in 1868, but then later won a Senate seat after leaving the presidency. He died in 1875 at age 66, five months into his senatorial term.