James Abram Garfield (November 19, 1831 – September 19, 1881) was the 20th president of the United States, serving from March 4, 1881, until his death six months later—two months after he was shot by assassin Charles J. Guiteau. A lawyer and Civil War general, Garfield served nine terms in the United States House of Representatives and is, to date, the only sitting member of the House to be elected president. Before his candidacy for the White House, he had been elected to the U.S. Senate by the Ohio General Assembly—a position he declined when he became president-elect.

Garfield was born into poverty in a log cabin and grew up in northeastern Ohio. After graduating from Williams College, he studied law and became an attorney. He was active in the Stone-Campbell Movement denomination. Garfield was elected as a Republican member of the Ohio State Senate in 1859, serving until 1861. He opposed Confederate secession, was a major general in the Union Army during the American Civil War, and fought in the battles of Middle Creek, Shiloh, and Chickamauga. Garfield was elected to Congress in 1862 to represent Ohio's 19th district. Throughout his congressional service, he firmly supported the gold standard and gained a reputation as a skilled orator. He initially agreed with Radical Republican views on Reconstruction but later favored a Moderate Republican-aligned approach to civil rights enforcement for freedmen. Garfield's aptitude for mathematics extended to a notable proof of the Pythagorean theorem, which he published in 1876.

At the 1880 Republican National Convention, delegates chose Garfield, who had not sought the White House, as a compromise presidential nominee on the 36th ballot. In the 1880 presidential election, he conducted a low-key front porch campaign and narrowly defeated the Democratic nominee, Winfield Scott Hancock. Garfield's accomplishments as president included his resurgence of presidential authority against senatorial courtesy in executive appointments, a purge of corruption in the Post Office, and his appointment of a Supreme Court justice. He advocated for agricultural technology, an educated electorate, and civil rights for African Americans. He also proposed substantial civil service reforms, which were passed by Congress in 1883 as the Pendleton Civil Service Reform Act and signed into law by his successor, Chester A. Arthur.

Garfield was a member of the intraparty "Half-Breed" faction who used the powers of the presidency to defy the powerful "Stalwart" New York senator Roscoe Conkling. He did this by appointing Blaine faction leader William H. Robertson to the lucrative post of Collector of the Port of New York. A fracas ensued that resulted in Robertson's confirmation and the resignations of Conkling and Thomas C. Platt from the Senate.

On July 2, 1881, Charles J. Guiteau, a disappointed and delusional office seeker, shot Garfield at the Baltimore and Potomac Railroad Station in Washington. The wound was not immediately fatal, but managed to kill Garfield on September 19, 1881, due to infection caused by his doctors' unsanitary methods.