This Colt M1911 was shipped August 3rd, 1917 to the U.S. Marine Corps Depot Quartermaster in Philadelphia PA in a 400 gun shipment. All M1911 USMC contract pistols are marked "U.S. Army" on the left side of the slide. There were very limited amounts of M1911's shipped directly to the USMC and are normally very tough to find in any condition. They are only identified by their serial number range.
This particular pistol is finished in Colt's brushed blue finish. Shortly after this pistol was produced Colt would switch to the "Black Army" finish which is much more course and did not hold up well over time.
This particular pistol is marked with the cartouche of "GHS" for Major Gilbert H. Stewart. Major Stewart was the inspector of ordnance from September 30th, 1914 to January 12th, 1918. His inspectors initials are on M1911's from Serial Number range 101,500-230,000 and M1917 revolvers ranging from 1-30,000.
Accompanying this pistol is a M1912 USMC holster with the embossed "USMC" marking on the flap.