America’s ninth president barely lasted a month in office. William Henry Harrison wasn’t assassinated like some of our later entries but died in 1841 of an acute illness originally diagnosed as pneumonia.

The longstanding belief was that Harrison fell ill after delivering a nearly two-hour Inaugural Address in wet, freezing-cold weather without a jacket, hat or gloves. But in 2014, epidemiologists concluded that Harrison’s chief symptoms—fatigue and severe abdominal distress—pointed to typhoid contracted from tainted drinking water.

Harrison wouldn’t be the last president to fall victim to Washington, D.C.’s lack of a sewage system, but he safely holds the title of the shortest-serving American president.

On July 2, 1881, President James A. Garfield arrived at Washington, D.C.’s Baltimore and Potomac Train station to begin a much-needed vacation. With his two sons in tow, Garfield looked forward to visiting his alma mater, Williams College, where he was scheduled to give a speech. At the time, presidents and their families traveled alone without a Secret Service detail.

What Garfield didn’t know was that a disgruntled (and unhinged) man named Charles Guiteau had been stalking the president for weeks, hoping to carry out a “God-given” command to kill Garfield to make way for his successor, Vice President Chester A. Arthur. Guiteau had even purchased an ivory-handled pistol that he thought would look nice in a museum when the deed was done.

Guiteau shot Garfield twice at close range, the second bullet lodging in the president’s pancreas. Incredibly, Garfield survived the shooting, but died months later after incompetent doctors failed to remove the bullet, leading to an agonizing and lethal infection. Garfield finally passed away on September 19, 1881, one day shy of 200 days in office.

President Zachary Taylor was a decorated war hero from the War of 1812 and the Mexican-American War, but ultimately it was a battle with bacteria that killed him.

Taylor, the 12th U.S. president, took office in March 1849. A year later, he attended Fourth of July celebrations in the nation’s capital on a sweltering summer day. To cool down, he drank glass after glass of ice water. When he got back home, he reportedly ate “large quantities” of cherries and other fruits washed down with iced milk.

It’s not clear which of these foods or drinks did him in, but like President Harrison less than a decade earlier, Taylor experienced excruciating stomach pain, vomiting and diarrhea. He died on July 9, 1850 from what his doctors diagnosed as cholera, a bacterial infection of the small intestine.

On the evening of August 2, 1923, Warren G. Harding was a popular president looking ahead to a reelection campaign, when he slumped over in his bed in the presidential suite of San Francisco’s Palace Hotel and died from what doctors now believe was a massive heart attack.

Harding suffered from poor health and exhaustion for years, possibly due to an enlarged heart. In the weeks before his death, Harding had embarked on an ambitious, cross-country speaking tour, including the first presidential visit to the Alaska Territory. He was hit with a bout of food poisoning and detoured to San Francisco for some bed rest and medical attention.

Harding’s sudden death shocked the nation, and the president’s legacy was first tainted by revelations that he had fathered an illegitimate child, and then the Teapot Dome Scandal, which exposed far-reaching bribery and corruption schemes that took place under Harding’s watch.

In his own words, Gerald Ford became president “under extraordinary circumstances never before experienced by Americans.” On August 9, 1974, President Richard Nixon resigned the presidency because of the Watergate scandal. According to the 25th Amendment to the Constitution, that automatically made Ford, Nixon’s vice president, the nation’s 38th president.

President Ford’s tenure was exceptional for other reasons. In 1973, Nixon appointed Ford, then a popular Republican congressman, to replace Vice President Spiro Agnew, who resigned due to an unrelated political scandal. That made Ford the only person to serve as both vice president and president without being elected.

In the 1976 presidential election, Ford lost to Democrat Jimmy Carter and left office on January 20, 1977, a term of exactly 895 days.

Like Ford, Millard Fillmore is one of the luckier presidents on this list, since his short term didn’t end in death. Fillmore was Zachary Taylor’s vice president, and became president in 1850 after Taylor’s sudden demise from the cherries-and-milk incident.

Like Taylor, Fillmore was a member of the Whig party, which formed in opposition to Democrat Andrew Jackson in the 1830s. Fillmore’s short tenure coincided with escalating political tensions between slave-owning and free states. In 1850, Fillmore signed into law the Fugitive Slave Act, which imposed fines and imprisonment on anyone aiding a runaway slave.

When Fillmore’s remaining term ran out, he campaigned for his party’s presidential nomination in 1852, but lost out to fellow Whig Winfield Scott. Fillmore was the last Whig president and the last president to not be affiliated with either the Democratic or Republican parties.

Like Warren Harding, President John F. Kennedy was a highly popular president who had just embarked on a weeks-long, nationwide tour to broadcast his political priorities—education, conservation and world peace—in expectation of a reelection campaign in 1964.

Kennedy was assassinated on November 22, 1963 as his open-air motorcade drove through Dallas, Texas. Gunman Lee Harvey Oswald was quickly arrested and charged with the president’s murder, but Oswald himself was gunned down by nightclub owner Jack Ruby as he was being transported to county jail.

As a shocked nation mourned, Vice President Lyndon Johnson was hastily sworn in as the 36th president.