|Years of service||1910–1941, 1945–1949|
|Commands held||Chief of the Hellenic Army General Staff|
|Wars||Balkan Wars, Macedonian Front, Greco-Turkish War of 1919–22, Greco-Italian War, Greek Civil War|
|Awards||Cross of Valour in Gold (twice)|
Dimitrios Giatzis (Greek: Δημήτριος Γιατζής, 1891–1964) was a senior Greek Army officer who held senior commands during the Greek Civil War of 1946–49, serving as commander of First Army and Chief of the Hellenic Army General Staff in 1947–49.
Dimitrios Giatzis was born in Lamia in 1891, and enlisted in the Hellenic Army as a volunteer on 12 March 1910. Promoted to NCO, he took part in the Balkan Wars of 1912–13, and after studies at the NCO School was commissioned as an Infantry Second Lieutenant on 27 December 1914.
He subsequently fought on the Macedonian Front during World War I and in the Asia Minor Campaign, first as a company commander and later as a staff officer, being promoted to Lieutenant in 1917 and to Captain in 1920. In the interwar period he served successively as battalion commander, chief of staff of the 3rd Infantry Division, in the staff of II Army Corps, in the Administrative Directorate of the Ministry for Military Affairs, commander of VI Border Sector (1938–40) and briefly chief of staff of the Infantry Inspectorate, before assuming command of III Infantry Brigade in September 1940. During this period he advanced to Major (1923), Lt. Colonel (1931), and Colonel (1935).
He led III Brigade during the first months of the Greco-Italian War, and was appointed chief of infantry to 8th Infantry Division in January 1941, a post in which he remained until the Greek capitulation following the German invasion of Greece in April.
Following liberation he joined the re-forming Army, and was named briefly commander of the 2nd National Guard Division in January 1945, before assuming command of the 9th Infantry Division in the next month. On 15 May 1946, he was appointed commander of the newly re-established I Army Corps at Athens, and in February 1947 he became the first commander of the newly formed First Army at Volos. He was moved to the post of Chief of the Hellenic Army General Staff on 1 November, a post he held concurrently with the ad hoc function of Commander-in–chief of the Army following the disbandment of First Army in March 1948, until 20 January 1949, when he retired from service at his own request.
Dimitrios Giatzis died in 1964.
- Note: Greece officially adopted the Gregorian calendar on 16 February 1923 (which became 1 March). All dates prior to that, unless specifically denoted, are Old Style.
- "Αντιστράτηγος ΓΙΑΤΖΗΣ ΔΗΜΗΤΡΙΟΣ του ΧΡΗΣΤΟΥ, ΑΜ 7645". Συνοπτική Ιστορία του Γενικού Επιτελείου Στρατού 1901–2001 [A Concise History of the Hellenic Army General Staff 1901–2001] (in Greek). Athens: Hellenic Army History Directorate. 2001. p. 168. ISBN 960-7897-44-7.
Lt General Konstantinos Ventiris
| Chief of the Hellenic Army General Staff
1 November 1947 – 20 January 1949
Lt General Georgios Kosmas