Named in honor of John Foster Williams, the destroyer was laid down on 25 March 1918 at San Francisco, California, by the Union Iron Works plant of the Bethlehem Shipbuilding Corporation.

Arriving at Ponta Delgada on 11 June, Williams proceeded to Gibraltar, where she picked up information pertaining to minefields still in operation in the Adriatic Sea, for delivery to the Commander, Naval Forces, Eastern Mediterranean.

The destroyer visited Split, Kingdom of Serbs, Croats and Slovenes; Gallipoli, in the Dardanelles; and Trieste, Italy, where she operated as part of the US naval forces monitoring the local situation there.

The German invasion of Poland on 1 September 1939 began hostilities in Europe, and President Franklin D. Roosevelt immediately declared the United States' neutrality.

After a final refit at the Boston Navy Yard, she departed Charlestown, Massachusetts, on 18 September, bound for Canadian waters; and reached Halifax, Nova Scotia, two days later.

[1] As one of the 50 destroyers transferred to the British under lend-lease in return for leases on important base sites in the Western Hemisphere— Williams was selected as one of the six units slated for the Royal Canadian Navy.

Operating as a submarine depot ship at Halifax until deemed unfit for further duty "in any capacity" in August 1944, St. Clair was used as a fire-fighting and damage control hulk until 1946.