John Marshall Harlan was an American lawyer and politician who served as an associate justice on the U.S. Supreme Court. He is often called "The Great Dissenter" due to his many dissents in cases that restricted civil liberties, including the Civil Rights Cases and Plessy v. Ferguson. Many of Harlan's views expressed in his notable dissents would become the official view of the Supreme Court starting from the 1950s Warren Court and onward. His grandson John Marshall Harlan II was also a Supreme Court justice.
Born into a prominent, slave-holding family in Frankfort, Kentucky, Harlan experienced a quick rise to political prominence. When the American Civil War broke out, Harlan strongly supported the Union and recruited the 10th Kentucky Infantry. Despite his opposition to the Emancipation Proclamation, he served in the war until 1863, when he won election as Attorney General of Kentucky. Harlan lost his re-election bid in 1867 and joined the Republican Party in the following year, quickly emerging as the leader of the Kentucky Republican Party. After the 1876 presidential election, newly-inaugurated President Rutherford B. Hayes appointed Harlan to the Supreme Court.