Built in 1957, by Gulfport Shipbuilding Incorporated of Port Arthur, Texas (hull #506) as the Juno for the Suderman and Young Towing Company of Galveston, Texas.
In 1965, the Suderman and Young Towing Company renamed the tug as the Sea King.
Along with the Suderman and Young Towing Company of Houston, Texas. The Bay Houston Towing Company is part of a combined operating company, the G and H Towing Company of Houston, Texas.
In 2005, the tug was acquired by Salmon Bay Barge Line Incorporated of Seattle, Washington. Where she was renamed as the M. Luther.
In 2005, Salmon Bay Barge Line Incorporated renamed the tug as the Luther.
In 2018, the tug was "laid up" at Seattle, Washington. She was a single screw tug, rated at 2,400 horsepower.