After experiencing engine trouble on her first attempt at a transatlantic crossing, West Gate was unsuccessfully attacked by two German submarines in early July 1918 while returning to port for repairs.

The ship was laid down at the Columbia River Shipbuilding Company of Portland, Oregon under the name War Agate as part of an order for the British Admiralty.

[3] However, the USSB commandeered and received title to all private shipbuilding projects in progress in mid-1917, which included the still-incomplete War Agate.

[3] After making her way to New York, West Gate took on 6,700 tons of cargo that included locomotives, steel rails, and other materiel for the United States Army and departed in a convoy for France on 28 June.

While headed to St. John's in moderate seas under a cloudy sky, West Gate was attacked by two German submarines at 19:15 on 3 July.

[3] After taking on 7,187 long tons (7,302 t) of Army materiel, she departed for Bordeaux on 4 October in a convoy escorted by cruiser Denver.

[3] At 02:28 on 7 October, while about 250 nautical miles (460 km) south of Halifax,[6] West Gate's steering gear engine jammed, sending the ship veering sharply to the port.

[3] Chief Gunner's Mate Michael B. Wallrath, who had assisted in lowering three lifeboats while he remained on board, jumped overboard after seeing to it that all the boats were away.

When he climbed up on the deckhouse to cut free a life raft and leave the ship, he discovered six men huddled on deck.

After he managed to get back to the surface, he clung to floating wreckage for two hours until pulled aboard the very raft he had missed earlier.

[3] The U.S. Navy awarded Chief Gunner's Mate Wallrath a Letter of Commendation for his actions during the sinking of West Gate.