Bush was 64 years and 222 days old when he was inaugurated, in 1989. He succeeded Ronald Reagan, the nation's oldest President, becoming the first sitting Vice-president to be elected since Martin van Buren in 1836. A Navy veteran, Bush was President when the Cold War ended. He, along with John Adams, are the only Presidents whose sons have also become President. (Adams's son John Quincy Adams was President in 1824–1828; Bush's son George W. Bush was President in 2000–2008).
3. James Buchanan
The nation's 15th President was 65 years, 315 days old when he was inaugurated, in 1856. Buchanan inherited a tense political situation and did little to ease that tension. While he was President, Congress passed the Compromise of 1850 and the Supreme Court issued the Dred Scott decision. Buchanan's successor in the White House was Abraham Lincoln.
2. William Henry Harrison
The nation's first Whig President, Harrison was a war hero and was 68 years, 23 days old when he was inaugurated, in 1841. He also holds the distinction of the President who served the fewest days in office. Harrison died 32 days after being inaugurated, some historians think as a result of a cold that he caught while delivering his very long inaugural address. His Vice-president, John Tyler, assumed the Presidency.
The nation's 15th President was 65 years, 315 days old when he was inaugurated, in 1856. 
The nation's first Whig President, Harrison was a war hero and was 68 years, 23 days old when he was inaugurated, in 1841. He also holds the distinction of the President who served the fewest days in office. Harrison died 32 days after being inaugurated, some historians think as a result of a cold that he caught while delivering his very long inaugural address. His Vice-president, 
