The vessel, originally designated YN–110, was laid down 9 February 1944 by the Marine Iron and Shipbuilding Co., Duluth, Minnesota.

On 10 April 1945 Oneota steamed out into Lake Superior en route to the St. Lawrence River and the Atlantic Ocean.

Arriving Boston, Massachusetts, early in May, she remained in southern New England waters for a month, then headed for the Pacific Ocean.

There, on 2 April, she joined others of her task group in preparing nearby waters for atomic tests Able and Baker.

Between 13 September and 15 October she plied between Guam and Rota, then steamed east for the United States.