Upon graduating from the Infantry Officer Candidate School Lieutenant Colonel Tryon E. Tisdale served as an Instructor in The Officer Candidate Preparatory School with the IRTC, Fort McClellan, Alabama. | His subsequent duty assignments include: 1943 and 1944, Infantry School, Instructor and Advance Class student, Fort Benning, Georgia. He was then assigned as a Company Commander with the 305th Infantry, 77th Division, in the Philippines. He also served as their Regimental S-2, during 1945. While in Korea in 1946 he was assigned to the 32nd Infantry, 7th Infantry Division as Battalion S-2 and S-3 while in the 32d Infantry he was also Regimental S-4 during 1947. In 1948 he was assigned as Assistant G-2 with Headquarters 7th Infantry Division, Korea. He was also a student at The Army Language School of Monterey, California, in 1948. During 1949 and 1950 he was with Headquarters Army Security Agency, Washington, D.C. In 1950 he was appointed to the rank of Major. Subsequent assignments were in 1951 and 1952 U.S. Embassy, Tehran, Iran, as Assistant Army Attache, 1953 Assistant G-1, Headquarters The Infantry Center, 1954 Student, Advance Class The Infantry School, Fort Benning, Georgia; 1955 Commander 1st Battalion, 28th Infantry, 8th Infantry Division, Fort Carson, Colorado; 1956 Assistant Chief of Staff, G-1, Headquarters, 8th Infantry Division, Fort Carson, Colorado; 1957 and 1958 Assistant Commandant Intelligence and Special Weapons School, Oberammergau, Germany; 1959 student at the Armed Forces Staff College, Norfolk, Virginia, 1960 Military Advisory Group, Vietnam.