James Speed was an American lawyer, politician, and professor who was in 1864 appointed by Abraham Lincoln to be the United States Attorney General. Speed previously served in the Kentucky legislature and in local political offices.

The United States attorney general (AG) is the head of the United States Department of Justice, and is the chief law enforcement officer of the federal government of the United States. The attorney general serves as the principal advisor to the president of the United States on all legal matters. The attorney general is a statutory member of the Cabinet of the United States.