Medical Battalion, 27th Replacement Company. Commanders World War I Maj. Gen. John F. O'Ryan (16 July 1917); Brig. Gen. Charles L. Phillips (19 September 1917); Maj. Gen. J. F. O'Ryan (6 December 1917); Brig. Gen. C. L. Phillips (23 December 1917); Maj. Gen. J. F. O'Ryan (29 December 1917); Brig. Gen. C. L. Phillips (22 February 1918); Maj. Gen. J. F. O'Ryan (1 March 1918); Brig. Gen. Palmer E. Pierce (16 June 1918); Maj. Gen. J. F. O'Ryan (18 June 1918); Brig. Gen. Palmer E. Pierce (14 November 1918); Maj. Gen. J. F. O'Ryan (23 November 1918) World War II Maj. Gen. William N. Haskell (October 1940 – October 1941) Brig. Gen. Ralph McT. Pennell (November 1941 – October 1942) Maj. Gen. Ralph C. Smith (November 1942 – May 1944) Maj. Gen. George W. Griner Jr. (June 1944 – December 1945) References Bibliography Further reading Swetland, Maurice J., and Lilli Swetland. "These Men": "For Conspicuous Bravery Above and Beyond the Call of Duty ...". [Harrisburg, Pa.]: Military Service Pub. Co, 1940. Mitchell A. Yockelson, Borrowed Soldiers: Americans under British Command, 1918, Norman, OK: University of Oklahoma Press, 2008, . External links Pictorial History of the 27th Division, United States Army, 1940–1941 – New York State Military Museum on New York Heritage Digital Collections O'Ryan's Roughnecks 027th Infantry Division, U.S. Infantry Division, U.S. 027th Divisions of the United States Army National Guard United States Army divisions of World War I Infantry divisions of the United States Army in World War II Military units and formations established in 1917 Military units and formations disestablished in 1967