A Most Unusual Presidential Inauguration: Gerald Ford
It was unprecedented in the history of the United States of America.
An unelected Vice President was taking the oath of office and becoming the President of the United States.
It happened on August 9, 1974 at 12:00 P.M. At precisely 12:00 P.M.
The night before an embattled Richard Nixon finally said no more to the onslaught of the Watergate investigation. His Presidency crippled so badly by the 'third-rate' break-in, the President was rendered essentially powerless and told the nation he would resign 'effective tomorrow at 12 Noon Eastern Time'.
And so it was that Gerald R. Ford became President of the United States.
He was unelected because of the resignation less than a year earlier of then Vice-President Spiro Agnew. Why did Agnew resign? Criminal charges against him when he was Governor of Maryland. Ford was then nominated to take his place and less than a year later...well, as they say, the rest is history.