During the early stages of the War of 1812, actually this happened in late 1811, the governor of the Indiana Territory was worried about a group of Shawnee under the leadership of The Prophet. He and his brother, Tecumseh, were organizing Indian groups in an effort to stop treaties with settlers that surrendered large amounts of Indian territory. To make a very long story very short, the governor, William Henry Harrison, attacked Prophetstown on the Tippacanoe River. It was a disaster for two reasons: first, the Indians and their two leaders had already left the settlement, and second, Harrison had left his fort unprotected. The Indians had already attacked the fort and abandoned the territory. In his haste to report the outcome to President James Madison, Harrison wrote of a great victory at Tippacanoe before the outcome could possibly have been known. It was never refuted, but was obviously inaccurate.
Now, Tecumseh was not happy. In fact, according to legend, he put a curse on Harrison and all future US presidents.
Maybe you are cynical about such things, as I am. But...
William Henry Harrison, the same guy, was elected president in 1840 running under the motto "Tippacanoe and Tyler, too." He died 30 days after taking office.
Abraham Lincoln was elected president in 1860. He died in office.
James Garfield was elected president in 1880. He died in office.
William McKinley was elected president in 1900. He died in office.
Warren Harding was elected president in 1920. He died in office.
Frankiln D. Roosevelt was re-elected president in 1940. He died in office.
John F. Kennedy was elected president in 1960. He died in office.
Ronald Reagan was elected president in 1980, shot but survived.
George W. Bush elected (?) president in 2000. Brain dead in office.
What was the curse? All presidents elected in a year ending in zero would die in office. Maybe it's just a legend.