Between March 26-30, 1970, government troops suppressed demonstrations in support of Prince Sihanouk, resulting in the deaths of around 300 people.
On (probably) March 27, 1970, South Vietnamese troops South of Cambodia and the US first division of cavalry in the North crossed the border to pursue the Vietcong. The Vietcong responded with a defensive strategy.
On either 27 or 28 March 1970, Lon Nil, brother of Lon Non-sent to Kampong Cham to deal with pro-Sihanouk demonstrations was killed. The governor’s palace was stormed and several officials killed by the crowd- including two National Assembly deputies, Kim Phon and Sos Saoun. In Tonle Bet, Lon Nil was attacked by a mob of pro-Sihanouk workers from the Chup plantation, and was beaten to death in the town marketplace. Rumors persist that members of the crowd cut the liver from Lon Nil’s body, which was then taken into a Chinese restaurant, where the owner was ordered to cook and slice it. It was then served to people in the immediate area.
Elsewhere, demonstrators took over an administrative post, and killed a supporter of the Lon Nol regime trying to speak out. The demonstrations spread across the south of the country and soldiers opened fire in several locations.
On March 27, 1994, the first meeting of the Church of JC&LS (Mormons) meeting in Cambodia was held at a hotel, with a total of six members and nine investigators in attendance.
On March 28, 1957, after Korean Foreign Minister Choi Duk Shin visited Cambodia, he stated that the trip was worthwhile and it was the first time to show the Korean flag and Korean envoy to the Cambodian people.
From March 29–31, 1967, Australian Prime Minister Harold “all the way with LBJ” Holt visited Cambodia on a tour that also included Laos, South Korea, and Taiwan. He attended a gala reception hosted by Sihanouk, who gave a toast (READ) and Holt gave the following speech on his return.
On March 29, 1993, coordinated attacks with hand-grenades on four premises in Phnom Penh frequented or owned by Vietnamese-speaking persons resulted in 2 deaths and at least 20 injuries.
On March 29, 1994 : The foundation stone for the new Institut Pasteur in Phnom Penh was laid by the French Minister of Health, Mrs Simone Veil and Dr. Chhea Tang, Minister of Health of Cambodia in the presence of Prof. Maxime Schwartz, Director General of the Institut Pasteur. On the same day, UN Secretary-General Boutros Boutros-Ghali appointed Benny Widyono as special representative to Cambodia.
By March 30, 1972, police had arrested many officials faithful to Sihanouk, including the ex governors of Phnom-Penh and Kompong Cham, and 150 suspected Vietnamese communists in Phnom Penh. At the same time anti-Vietnamese sentiments intensified. Vietnamese civilians were expelled from their houses and in camps around Phnom-Penh. Four such camps located around the capital were said to have existed.
On March 30, 1973, under the provisions of the Paris Peace Accords signed on Jan. 27, 1973, the last U.S. combat troops departed South Vietnam, ending nearly 10 years of U.S. military presence in Vietnam, Cambodia and Laos.
On March 30, 1992, UNHCR began assisting the repatriation of Cambodian refugees from Thai border camps.
On March 30, 1956, Prince Sihanouk resigned (for the 6th time) after forming a government as Prime Minister on March 1, 1956.
On March 30, 1976, Cambodian Communist Party leaders signed a secret order authorizing purges within the Party itself. This was the beginning of the Khmer Rouge internal purges.
On March 30, 1997, 16 people were killed and over 100 wounded after 4 grenades were thrown into a crowd of Khmer National Party supporters rallying at Wat Botum. The crowd was being addressed by opposition politician Sam Rainsy at the time. An American national named Rob Abney was injured in the attack, which caused an FBI investigation- ultimately inconclusive.
On March 31, 1970, forces loyal to Prince Sihanouk supported North Vietnamese troops attacking Cambodian government positions- the first major escalation of the 1970-75 civil war. NVA forces occupied large parts of eastern Cambodia, temporarily reaching the outskirts of Phnom Penh.
March 31, 2009, Comrade Duch admitted responsibility for his crimes under the Khmer Rouge and asked for forgiveness at the ECCC. He later asked to be acquitted on the grounds he was not a senior regime leader.
On April 1, 1967, the Communist Party of Kampuchea (CPK) headed by Saloth Sar (Pol Pot) initiated an insurgency against the government in the Samlaut District of Battambang Province. Samlaut had a history of insurrection against the government.
On 1 April, 1975, Lon Nol resigned. Later that evening the town of Neak Luong (Prey Veng, about 60km SE of Phnom Penh) fell to advancing communist forces, despite ferocious resistance and following a three-month siege. This development opened the southern approach to the capital and freed up 6000 Khmer Rouge soldiers to join the forces besieging Phnom Penh. The capture of six 105-mm howitzers at Neak Luong became a further menace to the those defending the capital.
On April 1, 1998, 37 people, including 11 foreign journalists and a British diplomat, had crammed into a helicopter which crashed near Preah Vihear temple. The military had charged journalists $40 a head for the ride, while the normal payload was just 15 people. Nobody was seriously injured.
