Andrew Johnson became the 17th president of the United States at one of the most traumatic moments in American history - the death of Abraham Lincoln. His childhood was filled with poverty and similar bereavement, his father having died when he was four.
As a boy, he was apprenticed to a tailor. The foreman there taught him how to read and write. Throughout his presidency, he spoke out on behalf of small-time merchants and farmers, proclaiming loudly that government should keep its nose out of people's affairs.
Eventually Johnson opened a tailor shop of his own in eastern Tennessee, and it became a gathering place for local politicians, He rose from alderman to mayor to state legislator and then to Congress, the governor's mansion and the U.S. Senate.
As a champion of states' rights, Johnson was in favor of permitting slavery in newly-acquired territories but opposed secession. Indeed, he was the only Southern Senator to stand with the Union. In 1862, Lincoln appointed him military governor of Tennessee, and he became Lincoln's running mate in 1864.
As president, Congress opposed many of his plans for restoration of the Union. He was impeached for "high crimes and misdemeanors" when he tried to fire without cause his secretary of war, Edward M. Stanton. His trial dragged on from March through May of 1868, and he was acquitted by one vote.