Harrison, like so many other early presidents, was a Virginia plantation owner. His father had been signatory to the Declaration of Independence, and his brother a member of the United States Congress/House of Representatives.
When he was 18, Harrison enlisted in the army, and quickly rose through the ranks to become governor of Indiana. It was in this capacity that he defeated a rebellion of Native Americans under the leadership of Tecumseh. At the Battle of Tippecanoe in 1811, Tecumseh was killed; Harrison was promoted to general and fought with distinction in the War of 1812.
After the war, he was elected to various political offices, including the House of Representatives and the U.S. Senate. He was a candidate for President in 1836, but lost the election to Martin Van Buren. He was a candidate again in 1840, when he won largely because of his heroic military record and the fact that there had been a severe economic downturn. His vice president was John Tyler. Their campaign slogan of "Tippecanoe and Tyler too" is among the most famous in American politics.
It was an absurdly cold day, March 4, 1841, when Harrison was to take the oath of office. Nevertheless, he braved the weather with no coat on, and delivered the longest inaugural address in American history, at nearly two hours. During this address he caught a cold, which developed into pneumonia. He passed away a month later, the first American president to die in office.
In fact, all American presidents elected in a year ending with a 0 between 1840 and 1960 died in office, including Harrison, Abraham Lincoln, James Garfield, William McKinley, Warren Harding, Franklin Roosevelt and John F. Kennedy. This has been called "Tecumseh's curse", after the Shawnee leader Harrison killed in 1811. Ronald Reagan did not die in office, although he was elected in 1980.
Harrison's grandson, Benjamin Harrison, was also president, making the two of them the only grandparent-grandchild pair of presidents.