Three factors led to a resurrection of the concept: an outbreak of the American Indian Wars by tribes in Minnesota and on the Great Plains; the disinclination of paroled but not exchanged Federal troops to be used to fight them; and protests of the Confederate government that any use of paroled troops in Indian warfare was a violation of the Dix–Hill prisoner of war cartel. Gen. Gilman Marston, commandant of the huge prisoner of war camp at Point Lookout, Maryland, recommended that Confederate prisoners be enlisted in the U.S. Navy, which Secretary of War Edwin Stanton approved December 21. General Benjamin Butler's jurisdiction included Point Lookout, and he advised Stanton that more prisoners could be recruited for the Army than the Navy. The matter was then referred to President Lincoln, who gave verbal authorization on January 2, 1864, and formal authorization on March 5 to raise the 1st United States Volunteer Infantry for three years' service without restrictions as to use.