The news of moves to impeach Andrew Johnson in the House of Representatives in 1868 was greeted by a 50-gun salute from Republicans in Pennsylvania. His chances of surviving trial in a Senate dominated by Republicans after the Civil War looked hopeless.
Yet it was a Republican senator from Kansas, Edmund G. Ross, whose vote saved him.
Ross, who was a new senator, was worried that the conviction and dismissal of Johnson, a Democrat, would damage the presidency forever.
Ross's vote of "not guilty" made him a hated figure among Republicans but earned him a place in John F. Kennedy's Pro-files in Courage.
Andrew Johnson had also become a hated figure for Republicans after he succeeded to the presidency when Abraham Lincoln was assassinated. Lincoln had chosen Johnson as his running mate in 1864, even though he was a southern Democrat from Tennessee.
Johnson was of Irish descent. His grandfather had left Larne, Co Antrim, in 1750. He had once been a humble tailor whose wife, Eliza McCardle, had helped him learn to read and write. But he was one of the few southern Democrats who supported the Union in the Civil War, and Lincoln hoped that his presence on the ticket would rally more southern support against the Confederacy.
After the war ended, Johnson fell foul of the Republican-dominated Congress over the plan called Restoration to bring the secession states of the rebel South back into the Union. Johnson favoured a reconciliatory approach but the Republicans wanted to impose harsher terms and voted for the Reconstruction plan. This subjected the South to continued military rule but also tried to ensure that the freed black slaves were given their full rights.
The breaking point came when Johnson tried to dismiss the War Secretary, Edwin Stanton, who was in charge of Reconstruction. Congress had forced through a Bill preventing Johnson from sacking Stanton, but the President went ahead, although he was warned that he could be impeached. "Impeach and be damned," he replied.
Articles of impeachment accusing Johnson of "high crimes and misdemeanours" were soon voted in the House of Representatives and the Senate trial opened on February 25th, 1868.
Stanton had barricaded himself into his office and defied all attempts by his successor, Gen Lorenzo Thomas, to remove him. In the end Stanton poured him two shots of whiskey and they sat down together for a chat.
Johnson himself never appeared at his trial which he referred to contemptuously as "the show" but the public galleries were packed with women friends of members of Congress. The Washington Star commented favourably on the politicians' taste in female looks as "we looked and looked in vain for dozen plain-looking women in the galleries".
But as the weeks dragged on with tedious legal arguments (the senators were not allowed to speak) boredom set in. The English novelist Anthony Trollope was spotted asleep in the press gallery.
Other journalists sent notes to the Congressmen on the floor pretending they were from some of the pretty ladies and had a good laugh reading the replies.
In Johnson's defence it was argued that he could not be charged with removing Stanton from office as he was still barricaded in his office.
The Baltimore Gazette complained that "the greatest act known to the Constitution - the trial of a President of the United States - was raising "less interest in the public mind than a prize fight".
In those days there were only 54 senators instead of today's 100. A two-thirds majority was therefore 36. There were 35 sure votes for conviction and three doubtful Republicans. Two of them voted not guilty and then it was up to Ross to cast the vote which would decide Johnson's fate.
When he cast his not guilty vote, the Senate erupted. Johnson's lawyers rushed to the White House to tell him the good news. He reportedly called for whiskey and toasted the lawyers. But he could not even get the Democratic nomination in the next election and died seven years later just after winning a seat in the Senate.