The SS Rhaetia was a trans-Atlantic passenger ship on the Hamburg-American line. She was built in 1883 by Reiherstieg, Hamburg, Germany and was 351 feet long and 43 feet wide and weighed 3,458 tons. The steamship had a speed of 11 knots and was powered by compound engines that delivered 2000 I.H.P. to a single screw. The steel-hulled ship had three masts and one funnel. She carried 100 first class and 800 third class passengers.
In 1895 the ship was sold to the United States government and was renamed the Cassius and later the Sumner by the U.S. Army. She was wrecked off Atlantic City, New Jersey in 1916. Her running mates were the Rugia, Bohemia and the Moravia.