High Quality Content by WIKIPEDIA articles! The Marietta class monitors were a pair of ironclad river monitors laid down in the summer of 1862 for the United States Navy during the American Civil War. Construction was slow, partially for lack of labor, and the ships were not completed until December 1865, after the war was over. However the navy did not accept them until 1866 and immediately laid them up. They were sold in 1873 without ever having been commissioned.