<P> During the history of the United States, eight presidents have died in office . Of those eight, four were assassinated and four died of natural causes . In all eight cases, the Vice President of the United States took over the office of presidency as part of the United States presidential line of succession . </P> <P> William Henry Harrison holds the record for shortest term served, holding the office of presidency for 31 days before dying . Harrison was the first president to die while in office when he caught pneumonia and died on April 4, 1841 . On July 9, 1850, Zachary Taylor died from acute gastroenteritis . Abraham Lincoln was the first president to be assassinated . He was shot by John Wilkes Booth on April 14, 1865 . Sixteen years later, on September 19, 1881, President James A. Garfield was assassinated by Charles J. Guiteau . Nearly twenty years after that, President William McKinley died from complications after being shot twice by Leon Czolgosz . President Warren G. Harding suffered a heart attack, and died on August 2, 1923 . On April 12, 1945, Franklin D. Roosevelt collapsed and died as a result of a cerebral hemorrhage . The most recent president to die in office was John F. Kennedy, who was assassinated with two rifle shots on November 22, 1963, in Dallas, Texas . </P>

Who was the first president to die in office and who was he replaced by