Curse of Tippecanoe
The "curse" began when President William Henry Harrison (elected in 1840) died in office from pneumonia just one month after becoming President.  According to a folk tale, the "curse" happened because then-General Harrison had fought on Native American grounds during the 1811 Battle of Tippecanoe.  The battle was famous, and "Old Tippecanoe" became Harrison's nickname.  But the battle made the Native Americans so angry that they cursed his name.