Harold Royce Gross was a Republican United States Representative from Iowa's 3rd congressional district for thirteen terms. The role he played on the House floor, objecting to spending measures and projects that he considered wasteful, prompted Time magazine to label him "the useful pest."

Iowa's 3rd congressional district is a congressional district in the U.S. state of Iowa that covers its southwestern quadrant, which roughly consists of an area stretching from Des Moines to the borders with Missouri.