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William McKinley Assassination

Published June 22, 2026Updated June 20, 2026
Sep 1, 1901

Czolgosz arrives in Buffalo steeped in anarchist grievance

Before the attack, Leon Czolgosz brought a volatile mix of isolation, anti-state politics, and admiration for anarchist violence into Buffalo, where McKinley’s public schedule gave him an accessible target.

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  1. Czolgosz had become increasingly drawn to anarchist ideas and to the belief that political violence could answer social and economic injustice.
  2. McKinley’s open appearance schedule at the Pan-American Exposition gave him a chance to act against the most visible symbol of national authority he could reach.
Sep 5, 1901

McKinley visits the Pan-American Exposition and gives his Buffalo address

On the day before the shooting, McKinley toured the Pan-American Exposition and delivered a major speech endorsing reciprocity and expanding American trade.

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  1. McKinley appears before large crowds on the exposition grounds and delivers a speech emphasizing commerce, industry, and international reciprocity.
  2. He remains in Buffalo for another day of public appearances, including the Temple of Music reception scheduled for September 6.
Sep 6, 1901

Temple of Music reception turns into the assassination attack

During a public receiving line inside the Temple of Music, Leon Czolgosz approached with a revolver hidden beneath a handkerchief and shot President McKinley at close range.

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  1. 4:07 p.m.
    As McKinley greets members of the public, Czolgosz steps forward with his right hand wrapped in a handkerchief concealing a .32-caliber Iver Johnson revolver.
  2. Seconds later
    Czolgosz fires twice. One shot appears to glance off McKinley; the second enters his abdomen and causes the wound that proves fatal.
  3. Immediately after
    James B. Parker and others seize Czolgosz. McKinley reportedly tells the crowd not to injure the captured gunman.
  4. Within minutes
    McKinley is rushed across the exposition grounds to the emergency hospital for surgery.
Sep 6, 1901

Emergency surgery begins at the exposition hospital

Doctors opened McKinley’s abdomen, repaired visible damage to the stomach and intestines, and failed to locate the bullet during an operation performed under improvised fairground conditions.

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  1. Late afternoon
    Matthew D. Mann leads the operation with Herman Mynter and other Buffalo physicians assisting at the temporary exposition hospital.
  2. The surgeons close perforations in the stomach and intestines, but the bullet cannot be found and remains inside McKinley’s body.
  3. An X-ray machine on the grounds is not used, and Roswell Park does not arrive in time to direct the initial operation.
Sep 14, 1901

President McKinley dies at the Milburn House

After several days of guarded optimism, McKinley’s condition worsened from infection and gangrenous deterioration, and he died at 2:15 a.m. on September 14, 1901.

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  1. September 7–12
    McKinley is moved to the Milburn House and at first appears to improve, encouraging public hopes that he may recover.
  2. September 13
    His condition collapses as infection and gangrene spread around the wound track, ending the brief period of optimism.
  3. 2:15 a.m.
    McKinley dies with family and attendants nearby, triggering national mourning and the transfer of executive power.
Sep 14, 1901

Theodore Roosevelt is sworn in as president

Later the same day, Vice President Theodore Roosevelt took the oath of office at the Ansley Wilcox House in Buffalo and became the 26th president.

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  1. Morning
    Roosevelt returns to Buffalo after learning that McKinley’s condition has become hopeless and then fatal.
  2. 3:30 p.m.
    At the Ansley Wilcox House, Roosevelt is sworn in and pledges continuity after the national shock of McKinley’s death.
Sep 23, 1901

Czolgosz goes on trial for McKinley’s murder

Just over a week after the president’s death, Leon Czolgosz was tried in Buffalo on a first-degree murder charge in a remarkably compressed proceeding.

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  1. The court appoints counsel for Czolgosz, who refuses to cooperate fully with the defense and offers little resistance to the case against him.
  2. Prosecutors present eyewitness, medical, and confession evidence tying the shooting directly to McKinley’s death.
Sep 24, 1901

Jury convicts Czolgosz of murder

After only a brief deliberation, the jury found Czolgosz guilty of murdering President McKinley.

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  1. Closing arguments end quickly, and the case goes to the jury with little factual dispute about the shooting itself.
  2. About 30 minutes later
    Jurors return a guilty verdict, rejecting any attempt to separate the gunshot wounds from the death that followed.
Sep 26, 1901

Death sentence is pronounced

Two days after the verdict, the court formally sentenced Czolgosz to die in the electric chair.

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  1. The court fixes execution for the week beginning October 28, leaving almost no gap between conviction and punishment.
  2. Czolgosz shows little outward reaction as the legal aftermath of the assassination moves with unusual speed.
Oct 29, 1901

Leon Czolgosz is executed at Auburn Prison

Czolgosz was executed by electric chair at Auburn Prison less than eight weeks after the shooting.

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  1. Czolgosz is put to death in the electric chair at Auburn Prison after the state rejects efforts to delay the sentence.
  2. Prison officials destroy and bury the remains in a way intended to prevent the assassin from becoming a public martyr.
Jan 1, 1902

The Secret Service takes on regular presidential protection

McKinley’s murder created the modern expectation of continuous presidential security, and by 1902 the Secret Service had assumed that protective role.

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  1. The assassination exposes the risks of open public access to the president and prompts a lasting change in federal protective practice.
  2. Within the next year, the Secret Service is carrying out routine protection of the president as a continuing mission.
Sep 30, 1907

The McKinley National Memorial is dedicated

A memorial and tomb for McKinley was dedicated in Canton, Ohio, preserving the assassination as part of the public memory of his presidency.

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  1. Public ceremonies in Canton dedicate the memorial that becomes the president’s burial site and a focal point of remembrance.