President William McKinley was shot by anarchist Leon Czolgosz on September 6th, 1901, during a visit to the Pan-American Exposition at the Temple of Music in Buffalo, New York. He died eight days later of gangrene caused by the gunshot wounds. He was the third American president to have been assassinated in forty years – an era in which the USA had turned away from the serious work of building the nation after the civil war to the excesses of the gilded age, the reversal of civil rights gains, and the nation’s first colonial wars. His successor would handle things in a very different fashion, though one no less fond of war.
This is a section from the Ken Burns ‘The Roosevelts’ series about McKinley’s Assassination
And here is some original footage from his funeral