In 1941 the Mather led a convoy of 13 freighters through the ice-choked upper Great Lakes to Duluth, Minnesota, to begin supplying badly needed iron ore to U.S. steel mills as they geared up to support president Roosevelt's pledge that America would be the "Arsenal of Democracy" prior to our entry into World War II. The trip set a record for the earliest arrival of a bulk carrier in a northern port. This heroic effort was featured in the April 28, 1941 issue of Life magazine.
Retired from service in 1980, Mather underwent an extensive restoration program beginning in 1987 and was opened for public tours in Cleveland's Northcoast Harbor in 1991. In 1995 the American Society of Mechanical Engineers conferred National Engineering Landmark status on Mather for the following technological Great Lakes firsts: single marine boiler system, boiler automation, and dual bow thruster system.