The Deutschland made two voyages to the U.S. In the summer of 1916, she delivered a cargo of chemical dyes, medical drugs, gems, and mail to Baltimore, Maryland, then returned to Bremerhaven with a cargo of nickel, tin, and crude rubber. In the fall of 1916, she delivered a cargo of gems, securities, and medicinal products to New London, Connecticut, and returned with a cargo of silver bullion. Before the Deutschland could embark on a third voyage, relations between Germany and the U.S. deteriorated significantly, so she was converted to an armed U-boat, the U-155.
The Bremen departed Bremerhaven in September 1916 for Norfolk, Virginia. She reportedly carried funds which were to be used to pay an American firm to build more cargo submarines for Germany. She never arrived in Virginia, and her fate remains unknown.
To mail an item via the Deutsch Ozean-Reederi, the sender had to bring the mail to the Insurance Bank offices in either Berlin, Hamburg, or Bremen. The Insurance Bank would then issue an insurance certificate which bore an imprint of the 50 Mark Ozean-Reederei design, and which was valid for mailings up to the 50 Mark rate (up to 50 grams) The certificate had three detachable coupons, one each for the insurance bank, the agency bank, and the sender.