Wikipedia contributors. (2025, February 2). Killing of Brian Thompson. In Wikipedia, The Free Encyclopedia. Retrieved 01:26, February 3, 2025, from https://en.wikipedia.org/w/index.php?title=Killing_of_Brian_Thompson&oldid=1273511347
Harrison died at 12:30 a.m. on April 4, 1841, Palm Sunday, nine days after becoming ill and exactly one month after taking the oath of office; he was the first president to die in office.