20 Jul--French and Viet Minh representatives sign Geneva cease-fire. Vietnam is divided into northern and southern zones pending reunification elections to be held in 1956. 2 Aug--LtCol Victor J. Croizat, USMC, arrives in South Vietnam for duty with USMAAG. 8 Sep--Manila Pact signed by U.S. and seven other nations. Within weeks (Sep 1954) the Manila Pact is transformed into the Southeast Asia Treaty Organization (SEATO). 13 Oct--Premier Diem decrees the establishment of a 1,137-man Marine Corps (VNMC). 1955 Feb--LtCol Croizat becomes first advisor to VNMC. Apr--Sect rebellion threatens to topple the Diem government. Marine Landing Battalion deploys to the Mekong Delta. 31 May--Diem names Major Le Quang Trong as Senior Marine Officer of VNMC. Sep--Two USMC advisors, a captain and a technical sergeant, are assigned to the USMAAG, Vietnam, for duty with the VNMC. 23 Oct--Premier Diem receives 98 percent of South Vietnamese vote during a national referendum in which he was opposed by Bao Dai. 26 Oct--Ngo Dinh Diem proclaims the Republic of Vietnam and becomes the republic’s first president. 1956 18 Jan--Diem appoints Major Phan Van Lieu as Senior Officer of VNMC. Feb--Marine Landing Battalion returns to garrison at Nha Trang. VNMC reorganized into two landing battalions, a 4.2-inch mortar company, and a small headquarters. Jun--LtCol William N. Wilkes, Jr., replaces LtCol Croizat as Senior Marine Advisor to VNMC. Jul--Election deadline for reunification of northern and southern zones passes without serious incident. Aug--Diem appoints Captain Bui Pho Chi as Senior Officer of VNMC. Oct--Diem appoints Major Le Nhu Hung as Senior Officer of VNMC. Nov--LtGen Samuel T. Williams, USA, relieves LtGen John O’Daniel as Chief USMAAG, Vietnam. 1958 Jun--LtCol Frank R. Wilkinson, Jr., relieves LtCol Wilkes as Senior Marine Advisor to VNMC. 1959 May--1st VNMC Landing Battalion conducts operations against Viet Cong in An Xuyen Province while 2d Landing Battalion conducts similar operation against Communist guerrillas in Vinh Binh Province. 1 Jun--The VNMC is expanded to a Marine Corps Group of 2,276 officers and men. A 3d Landing Battalion is formed and the battalions are reorganized into four infantry companies. 1960 Jun--LtCol Clifford J. Robichaud, Jr., relieves LtCol Wilkinson as Senior Marine Advisor to VNMC. Sep--LtGen Lionel C. McGarr, USA, relieves LtGen Williams as Chief USMAAG, Vietnam. 11 Nov--An abortive attempt by ARVN paratroops and two Marine companies to overthrow the Diem Government. 20 Dec--The Communist “National Front for Liberation of South Vietnam” was formed. 1961