The second inauguration of Abraham Lincoln as president of the United States took place on Friday, March 4, 1865, at the East Portico of the United States Capitol in Washington, D.C. This was the 20th inauguration and marked the commencement of the second and final term of Abraham Lincoln as president and only term of Andrew Johnson as vice president. Lincoln was assassinated 42 days into this term, and Johnson succeeded to the presidency. Chief Justice Salmon P. Chase administered the presidential oath of office. This was the first inauguration to feature African Americans in the inaugural parade, and the first president in over 30 years to be inaugurated for a second term since the second inauguration of Andrew Jackson in 1833.

On April 14, 1865, Abraham Lincoln, the 16th president of the United States, was assassinated by John Wilkes Booth while attending the play Our American Cousin at Ford's Theatre in Washington, D.C. Shot in the head as he watched the play, Lincoln died of his wounds the following day at 7:22 am in the Petersen House opposite the theater. He was the first U.S. president to be assassinated. His funeral and burial were marked by an extended period of national mourning.