Samuel Drake Lockwood was an Illinois lawyer and politician who served as the state's Attorney General, Secretary of State, Justice of the Illinois Supreme Court and the state's trustee on the board of the Illinois Central Railroad.

The Illinois attorney general is the highest legal officer of the state of Illinois in the United States. Originally an appointed office, it is now an office filled by statewide election. Based in Chicago and Springfield, the attorney general is responsible for providing legal counsel for the various state agencies including the governor of Illinois and Illinois General Assembly, as well as conducting all legal affairs pertaining to the state.