Samuel Miller moved to Keokuk in 1850 and practiced law there until he was appointed Associate Justice of the United States Supreme Court in 1862. He served until his death 28 years later and was the first appointee to the high court from Iowa and from west of the Mississippi River. During his tenure he heard more than 5,000 cases and wrote 783 opinions, of which 141 related to constitutional law. His house is preserved as a museum by the Lee County Historical Society, and his gravesite is in Oakland Cemetery in Keokuk.