Turkey joined the North Atlantic Treaty Organization on 18 February 1952. On 11 June 1952, NATO authorities decided to establish Allied Land Forces Southeastern Europe (LANDSOUTHEAST) in Izmir to be commanded by a US general officer who would have Turkish and Greek general officers as his deputies.

The actual establishment of LANDSOUTHEAST occurred on 8 September 1952, when US General Willard G. Wyman assumed command and established his headquarters at Sirinyer.

Headquarters LANDSOUTHEAST was initially staffed by Turkish, Greek and US military personnel and NATO international civilians. In 1954, representation was extended to French, Italian and UK military personnel. It was at this time that LANDSOUTHEAST moved to the Sehir building in the Alsancak area in Izmir.

In 1966, the first major change occurred when French military personnel were withdrawn to be followed by the Greek personnel in 1974. On 30 December 1977, SHAPE and Turkish military authorities announced another change in the command structure of LANDSOUTHEAST to be effective as of July 1, 1978. The command billet was filled by a Turkish general officer with a US general officer as his deputy. On 30 June 1978, General Sam Walker handed over the command to General Vecihi Akin as the first Turkish commander at LANDSOUTHEAST.

A French Liaison Office was established in 1993. Two German Army officers were assigned to LANDSOUTHEAST in July 1994 for the first time in its history, and in August 1998 two Canadian Army Officers joined the LANDSOUTHEAST staff.

Construction of a new collocated headquarters facility in Sirinyer, Izmir was completed in March 1994 and LANDSOUTHEAST moved into the headquarters in April 1994. The headquarters garrison at Sirinyer was named General Vecihi Akin Garrison in March 1996, after the first Turkish LANDSOUTHEAST Commander.

Türkiye Kuzey Atlantik Antlasmasi Teskilati’na (NATO) 18 Subat 1952’de katilmistir. 11 Haziran 1952 tarihinde NATO makamlari, bir Türk ve bir Yunanli generalin yardimciliklarini yapacagi bir Amerikali generalin emir ve komutasinda görev yapacak olan NATO Güneydogu Avrupa Müttefik Kara Kuvvetleri Komutanliginin (LANDSOUTHEAST) Izmir’de kurulmasini kararlastirmislardir.

Amerikali Korgeneral Willard G. Wyman’in 8 Eylül 1952 günü komutanligi üstlenerek karargahini Izmir Sirinyer’de kurmasiyla LANDSOUTHEAST Komutanligi fiilen tesis edilmistir.

Komutanlikta baslangiçta Türk, Yunanli ve Amerikali askeri personel ile NATO statüsüne sahip sivil personel görev yapmis; 1954’te ise Fransiz, Italyan ve Ingiliz askeri personeli de göreve baslamistir. Ayni yil LANDSOUTHEAST Komutanligi Izmir Alsancak’taki Sehir Binasina tasinmistir.

1966’da Fransiz askeri personelinin komutanliktan ayrilmasiyla ilk önemli degisiklik meydana gelmis; 1974’te ise Yunanli personel komutanliktan ayrilmistir. 30 Aralik 1977 tarihinde NATO Avrupa Müttefik Kuvvetleri Yüksek Komutanligi (SHAPE) ile Türk askeri makamlari, LANDSOUTHEAST Komutanliginin komuta yapisiyla ilgili olarak 1 Temmuz 1978 tarihinden itibaren geçerli olmak üzere yeni bir degisiklik yapilacagini, açiklamislardir. Buna göre komutan kadrosu bir Türk generalince, komutan yardimcisi kadrosu da bir Amerikali general tarafindan doldurulacaktir. 30 Haziran 1978 günü Amerikali Orgeneral Sam Walker LANDSOUTHEAST Komutanligi görevini ilk Türk Komutan olan Orgeneral Vecihi Akin’a devretmistir.

1993 yilinda komutanlik nezdinde bir Fransiz Irtibat Subayligi kurulmustur. Temmuz 1994’te LANDSOUTHEAST Komutanliginin tarihinde ilk kez olmak üzere Alman Kara Kuvvetlerine mensup iki subay komutanlikta göreve baslamislar, Agustos 1998’de ise Kanada Kara Kuvvetlerine mensup iki subay karargaha katilmistir.

Izmir Sirinyer’deki yeni Müsterek Karargah Binasi tesislerinin insasi Mart 1994’te tamamlanmis ve LANDSOUTHEAST yeni karargah binasina Nisan 1994’te tasinmistir. Karargahin bulundugu Sirinyer’deki kislaya 1996 yilinin Mart ayinda LANDSOUTHEAST’in ilk Türk Komutani olan Orgeneral Vecihi Akin’in adi verilmistir.