Liuetenant Colonel Catherine G. Sinnott began her Army career in Nashville, TN, in 1908. She took 2 years training at St. Thomas Hospital Training School and was associated with the hospital for 6 years, rising to the post of assistant superintendent of nurses and chief of the operating room.

When war broke out in 1917, Sinnott was one of a group of 20 nurses and 30 doctors who organized the Vanderbilt unit for overseas service, she serving as chief nurse for the group. When she returned to the United States, after a total of 26 months in France, she went to Camp Dix, NJ, then to Washington D.C. with the Army dispensary.

Sinnott was one of a group of 31 Army nurses cited for deeds of outstanding bravery and merit. Miss Sinnott won her Distinguished Service Medal for her service in France, including the evacuation of 7,000 of the 11,000 nurses after the armistice. She was a victim of mustard gas, and when her hospital was bombed, she did magnificent work in removing patients.