April Revolution

On April 24, 1965, three junior officers requested a meeting with President Donald Reid Cabral, who rejected the offer after he had received news of a suspected anti-government plot. When Chief of Staff Riviera Cuesta was instead sent to discuss with the officers at the August 16 military camp, he was immediately detained. A group of military constitutionalists and Dominican Revolutionary Party (DRP) supporters then seized the Radio Santo Domingo building and issued calls of sedition while Constitutionalist officers distributed weapons and Molotov cocktails to their civilian comrades. The transmissions prompted the garrison of the February 27 camp and a unit of the Dominican Navy's frogmen to defect. Large numbers of police officers abandoned their positions and changed into civilian clothing.^[8]

The following day, Reid appointed General Wessin y Wessin as the new chief of staff. Wessin rallied the government troops, branded them Loyalists, and announced his plans of suppressing the rebellion. At 10:30 am rebels stormed the presidential palace and arrested Reid. Several hours later, four Loyalist P-51 Mustangs conducted aerial bombings of the National Palace and other Constitutionalist positions, and one plane was shot down by ground machine-gun fire during the incident.^[9] A single Loyalist vessel, Mella, on the river Ozama, also bombarded the palace. Fearing that a mob, which had gathered at the palace, would lynch Reid, the rebel commander Francisco Caamaño allowed him to escape, as Reid had already lost the support of the Loyalists. The majority of the DRP leadership fled the capital, and Constitutionalists mobilized a total of 5,000 armed civilians and 1,500 members of the military.^[7][8] On April 26, José Rafael Molina Ureña was declared the provisional president, and large crowds gathered in the streets to demand Bosch's return from exile.

US intervention

Wounded American soldier in Santo Domingo, 1965.

In the meantime, US diplomats in Santo Domingo initiated preparations for evacuating 3,500 U.S citizens. In the early morning of April 27, a group of 1,176 foreign civilians who had assembled in Hotel Embajador were airlifted to the Bajos de Haina naval facility, where they boarded USS Ruchamkin and USS Wood County, as well as the helicopters of HMM-264, which evacuated them from the island to USS Boxer and USS Raleigh. Later that day, 1,500 Loyalist troops, supported by armored cars and tanks, marched from the San Isidro Air Base, captured Duarte Bridge, and took position on the west bank of the Ozama River. A second force, consisting of 700 soldiers, left San Cristóbal and attacked the western suburbs of Santo Domingo. Wessin y Wessin ordered his armored units to cross the Duarte Bridge into Santo Domingo's center. However, the tanks quickly became bogged down in fierce combat within the narrow streets; armed civilians destroyed them. Unable to advance, the Loyalists retreated to San Isidro. The battle resulted in hundreds of casualties.

Rebels overran the Fortaleza Ozama police headquarters and took 700 prisoners. On April 28, armed civilians attacked the Villa Consuelo police station and executed all of the police officers who survived the initial skirmish. One US Marine battalion landed in Haina and later moved to Hotel Embajador, where it provided assistance in the upcoming airlifts. During the night, 684 civilians were airlifted to USS Boxer. One US Marine was killed by a rebel sniper during the operation.^[8] On April 29, the US ambassador to the Dominican Republic, William Tapley Bennett, who had sent numerous reports to US President Lyndon Johnson, reported that the situation had reached life-threatening proportions for US citizens and that the rebels were Communists. Bennett stressed that the US had to act immediately, as the creation of an international coalition would be time-consuming. Contrary to the suggestions of his advisers, Johnson authorized the transformation of evacuation operations into a large-scale military intervention through Operation Power Pack, which was aimed to prevent the development of what he saw as a second Cuban Revolution.^[7][8][10] It was the first overt U.S. military intervention in Latin America in more than 30 years, although it came on the heels of U.S.-backed coups in Guatemala and Brazil, as well as ongoing covert operations in Cuba.^[11]

International Security Zone map.

At 2:16 a.m. on April 30, 1965, the 3rd Brigade of the 82nd Airborne Division landed at the San Isidro Air Base and started the US military intervention in the conflict. During the next couple of hours, two brigade combat teams and heavy equipment were also dispatched. At sunrise the 1st Battalion, 508th Infantry Regiment moved up the San Isidoro highway under the cover of F-4 Phantom jets flying from Puerto Rico, securing a position east of the Duarte bridge. More units of the 82nd Airborne landed and secured the entire east bank of the Ozama River. Rebel positions across the river were destroyed by 105 mm howitzers. U.S. soldiers crossed the bridge and occupied a six-block area on the western side of the Duarte Bridge, but suffered casualties from sniper fire. The 1st Battalion 505th Infantry Regiment remained at the airbase and sent out patrols to the perimeter. A force of 1,700 Marines of the 6th Marine Expeditionary Unit occupied an area containing a number of foreign embassies. The locale was proclaimed an International Security Zone by the Organization of American States (OAS). Earlier in the day, the OAS also issued a resolution calling the combatants to end all hostilities. At 4:30 p.m., representatives of the loyalists, the rebels, and the US military signed a ceasefire that was to take effect at 11:45 p.m. That timing favored the demoralized Loyalists, who had lost control of Ciudad Colonial.^[8][12]

On May 5, the OAS Peace Committee arrived in Santo Domingo, and a second definite ceasefire agreement was signed, which ended the main phase of the civil war. Under the Act of Santo Domingo, the OAS was tasked with overseeing the implementation of the peace deal as well as distributing food and medication through the capital. The treaties failed to prevent some violations such as small-scale firefights and sniper fire. A day later, OAS members established the Inter-American Peace Force (IAPF) with the goal of serving as a peacekeeping formation in the Dominican Republic. The IAPF had 1,748 Brazilian, Paraguayan, Nicaraguan, Costa Rican, Salvadoran and Honduran troops and was headed by Brazilian General Hugo Panasco Alvim, with US Army General Bruce Palmer serving as his deputy commander.^[1][12] General Palmer proposed sending U.S. troops to eliminate the northern rebel sector and shut down the rebel-held radio station, but Washington blocked any offensive operations involving U.S. troops.

Francisco Caamaño, rebel leader in Dominican War of 1965.

Utilizing Radio Santo Domingo as their primary weapon, the rebels launched a psychological campaign against the United States, the OAS, and the Loyalists. Through numerous outlets, studios, and transmission sites nationwide, they employed Radio Santo Domingo to incite a nationwide rebellion. In response, American forces initiated jamming operations, deploying Army Security Agency (ASA) units on land, air force units in the skies, and naval ships at sea. Additionally, a reinforced company from the army's 7th Special Forces Group, led by Col. Edward Mayer, attacked critical relay sites beyond the capital. Their initial efforts were not effective, however, and rebel broadcasts continued to make their influence felt countrywide.^[13]

On May 13, the Loyalists launched an air attack on Radio Santo Domingo and its main transmitter sites. One of the planes accidentally strafed U.S. troops, prompting the Americans to return fire and shoot down another P-51 of World War II vintage.^[14] The following day, the Loyalists initiated an offensive against the rebel-held northern sector. They overwhelmed the rebels' initial defense line, seizing control of the majority of the city's industrial sector. By May 20, the Loyalists had completed the destruction of the rebel northern zone and captured Radio Santo Domingo.