Associated Press

On Sept. 14, 1901, President William McKinley died in Buffalo, New York, of gunshot wounds inflicted by an assassin eight days prior; Vice President Theodore Roosevelt succeeded him, becoming the youngest U.S. president at age 42.

In 1982, Princess Grace of Monaco, formerly film star Grace Kelly, died at age 52 of injuries from a car crash the day before.

In 2001, Americans packed churches and public squares on a day of remembrance for the victims of the Sept. 11 attacks. President George W. Bush prayed with his Cabinet and attended services at Washington National Cathedral then flew to New York, where he waded into the ruins of the World Trade Center and addressed rescue workers.

In 2012, fury over an anti- Muslim film ridiculing the Prophet Muhammad sparked violent clashes across the Muslim world.