He was barely eligible to become a president. It states in the constitution that to become president, one must be born in the United States. Jackson was Scots-Irish (now known as Orange Irish...descended from Scottish protestants put in what is today Northern Ireland in the 1600s to try to convert the Catholics). He was conceived in Northern Ireland and born shortly after his mother arrived in America.
He was a mamma's boy. The reason he hated Native Americans so much was that they threatened his mother when he was little, and he couldn't do anything about it.
He won the Battle of New Orleans in the War of 1812 after the treaty ending the war was signed. It took so long in those days to get the news out that fighting could happen a month after the war was officially over.
A statue of Jackson and his horse in New Orleans was the first successful equestrian statue with only two legs attached to the base.
Jackson married a woman named Rachael. She thought her first husband was dead because he went off to fight the Indian Wars, and didn't come back. Just around the time she was marrying Jackson, her first husband showed up and accused her of polygamy. She died while Jackson was running for president, allegedly because of harassment from the scandal surrounding the end of her first marriage.
Jackson was a known dueler. He had a bullet in his chest through his presidency, and he killed a man in a duel while in office.
He had a notoriously short temper.
He is considered the father of American Democracy. The US was, and still is, officially a republic. Jackson was the first "Common Man" president, coming from poor roots (his family were immigrants, and he grew up in the backcountry).
Jackson's innauguration was the biggest drinking party in Washington, D.C.'s history at the time. He invited his old army buddies and his wild neighbors from the backcountry where he grew up, and the White House staff, wanting badly to go to sleep, put the alcohol out on the lawn and locked the doors behind the guests who went out to get to it in order to get peace and quiet.
AP US History