Royal Cleaves Johnson (October 3, 1882 – August 2, 1939) was a U.S. Representative from South Dakota and a highly decorated veteran of World War I while he was still a member of Congress. Despite voting against United States declaration of war on Germany, he took a leave of absence from Congress to enlist. He became a highly decorated veteran receiving the Distinguished Service Cross from the United States government. He also received the War Cross 1914–1918 from the French government.