The Curse of Tippecanoe is a belief that any US President elected in a year that ends in a zero (0) will not finish their term alive. It all started because of the death of William Henry Harrison, the ninth US President, back in 1841. Harrison died just after one month of being in the office, due to pneumonia. The curse was named after the location where Harrison, known for defeating Native Americans at the Battle of Tippecanoe, fought his battles.
People believe that the curse is the revenge of the Native American leader, Tecumseh, for the defeat at the Battle of Tippecanoe. But there is no real proof that Tecumseh ever cursed Harrison or the office of the president. It is just a legend or a superstition that people continue to believe.
However, it's not true that every US President elected in a year ending with zero did not finish their term. For example, Ronald Reagan, George W. Bush, and Barack Obama were all elected in years ending with zero and completed their terms in office.
So, while the curse may be a popular tale or urban legend, there is no factual basis for it. It's just a story that people tell to add a little bit of extra mystery and intrigue to the presidency.