On April 6, 1841, John Tyler is sworn in as president. Tyler was elected as William Harrison’s vice president earlier in 1841 and was suddenly thrust into the role of president when Harrison died one month into office. He was the first vice president to immediately assume the role of president after a sitting president’s untimely exit and set the precedent for succession thereafter.

Tyler was a proponent of states’ rights and the perpetuation of slavery, and as such was a threat to his own political party, the Whigs, who advocated a strong federal system. When Tyler vetoed his fellow Whigs’ attempt to reestablish the National Bank, most of his cabinet resigned and he was thrown out of the Whig Party. As he had previously alienated the support of the Democrats by denouncing Andrew Jackson’s policies, Tyler became a president without a party who received death threats from both sides and earned the enmity of Congress. His four years in office were contentious, though he is credited with settling Canadian border disputes with Britain and beginning the annexation of Texas.

In 1844, during a cruise down the Potomac aboard the newly commissioned steam frigate USS Princeton, Tyler himself narrowly escaped death. The ship’s state-of-the-art cannon, called the Peacemaker, exploded when the crew fired a celebratory salute, killing several people aboard, including two members of Tyler’s cabinet and his future wife’s father. Tyler’s unexpected ascendance to the presidency and the near-miss aboard the Princeton earned him the nickname of His Accidency.

After leaving the White House, Tyler tried to broker a peace convention between the North and South on the eve of the Civil War, but failed to reach an agreement with Abraham Lincoln on key issues. Denounced as a traitor by the North, Tyler fell in line with southern secessionists and, in 1861, was elected to the Confederate House of Representatives. He died in 1862.