Picket was completed 15 April 1942 by Marietta Manufacturing Co., Point Pleasant, West Virginia, as the U.S. Army mine planter USAMP-1 General Henry Knox as the first of the WW II period planters built for the U.S. Army Mine Planter Service. USAMP Knox was transferred to the U.S. Navy 2 January 1945; completed conversion to an Auxiliary Minelayer, ACM-8, at Charleston Navy Yard 5 March 1945; and commissioned 6 March 1945, Lt. Robert F. Harwood in command.