Service history On 17 July 1899 troops from Colorado boarded the transport in Manila for return to the United States as a typhoon was building in the
South China Sea forcing overnight suspension of boarding. On the 18th boarding was completed and the ship sailed, and with a period taking shelter in the lee of Formosa, reached
Nagasaki 25 July 1899. After coaling the ship sailed on 27 July reaching
Yokohama on 30 July and departing on 2 August to reach San Francisco on 16 August. The ship docked the next day after clearing quarantine. On 30 December 1900
Warren while getting underway at Manila for a voyage to the United States ran into the British ship
Mogul.
Warren was found to be at fault with the first assistant engineer, in charge, turning control over to the second assistant engineer who did not follow engine orders. Both engineers were dismissed from the transport service. Claims were disputed in particulars but referred to Congress for final payment. In the summer of 1902 the ship transported Dr.
Sheldon Jackson from Seattle to Nome in connection with his work with introducing reindeer into Alaska. Forty-three Filipino political prisoners had been deported to Guam by General
Arthur MacArthur Jr. for their loyalty to the
Philippine Revolution during the
Philippine–American War. On 21 September 1902
Warren embarked most of the political prisoners exiled to Guam for return to the Philippines.
Warren, on the way from Manila to San Francisco, entered Honolulu on 10 July 1905 with a missing propeller blade. Honolulu was the normal coaling stop and the ship had entered the port four years earlier with two missing blades. In that case the ship had left Honolulu for Manila and returned after several days for repairs. Those were done by piling coal and pig iron on the forward decks and removing heavy material from aft so that the stern was raised out of the water enough for the repairs. The same was planned in this case, though the ship might be able to make San Francisco at reduced speed without the repair. During August 1914 the
Insular Government of the Philippine Islands dealt with stabilizing the market for staple goods in a crisis related to shipping at the start of war with Germany. With regard to rice the government obtained the cooperation of the Army command in using
Warren to transport rice from
Indo-China for government sale to dealers. The general commanding U.S. Army forces in the Philippines was directed on 3 August 1918 to send the 27th and 31st Infantry Regiments, a field hospital, ambulance company and a telegraph company to Vladivostok with
Warren, and
Merritt designated as transports. Elements of the
27th Infantry Regiment were embarked aboard
Warren sailing 7 August 1918 arriving 15 August. Other trips involved transport of ambulance and field hospital elements in September. In 1920
Warren made voyages to
Vladivostok to evacuate elements of the
Czech Legion disembarking them at
Trieste, Italy. == Sinking ==