[20] Its first public action took place on 29 May 1970, with the kidnapping, subsequent revolutionary trial and assassination of the anti-Peronist ex-dictator Pedro Eugenio Aramburu, one of the leaders of the 1955 coup that had overthrown the constitutional government led by President Juan Domingo Perón.

Its actions contributed to the military dictatorship calling free elections in 1973, in which the multi-party electoral front of which it was a member (Frejuli) won, with the presidential candidacy of Peronist Héctor José Cámpora, a man close to Montoneros, as well as several governors, parliamentarians, ministers and high-ranking government officials.

[24] Cámpora's government and its relationship with the Montoneros came under heavy pressure from the outset, from right-wing sectors and the Italian anti-communist lodge Propaganda Due and the CIA, and just 49 days later he had to resign after the Ezeiza massacre.

Montoneros established its leadership in Mexico and fought the dictatorship, inflicting serious casualties on the civil-military government and suffering heavy losses, including a large number of militants and fighters who disappeared.

Priest and sociologist, political fighter and agitator, student and mass leader, he satisfied his thirst for justice by joining the armed struggle when he understood that the oligarchy shuts all roads and confronts the people with its ultimate weapon—violence ... Camilo represents contradiction, scandal, probing, unity, sacrifice, action, violence, and commitment.

With Camilo, we believe that revolution is the only efficient and meaningful way to achieve love for all.Richard Gillespie identifies Cristianismo y Revolución as the decisive factor behind the radicalization of Catholic students and the creation of Montoneros, along with the Movement of Priests for the Third World.

Elorrio also pushed his readers towards action and revolution, writing: "I had to fight with the slaves, the people, as they fought, not as an elitist teacher who tells them what is good and what is evil and then goes back to his study to read Saint Augustine, but as a genuine participant, with them not for them, in their misery, their failings, their violence...

Donald C. Hodges notes that the ideology of Camilo Torres Commando was identical to that of Montoneros, representing "a fusion of Camilist, Guevarist, and Cookist themes combined with the cult of Evita Peron".

Although Guevara came from an Argentine anti-Peronist family, he visited Perón in Madrid and was deeply impressed by his political thought, praising Peronism as "indigenous Latin American socialism with which the Cuban Revolution could side".

[70] In April 1973, Colonel Héctor Irabarren, head of the 3rd Army Corps' Intelligence Service, was killed when resisting a kidnap attempt by the Mariano Pojadas and Susana Lesgart platoons of the Montoneros.

[69] On 17 October 1972, a powerful bomb detonated inside the Sheraton Hotel in Buenos Aires, with nearly 700 guests at the time, killing a Canadian woman (Lois Crozier, travel agent from West Vancouver) and gravely wounding her husband Gerry as he slept.

[78] Perón himself did not desire to abandon the Montoneros and sought to restore his trust in his last speech from June 1974, where he denounced "the oligarchy and the pressures exerted by imperialism upon his government", which was considered an implication that he was being manipulated by the Peronist right.

On 22 February 1975, in an ambush in the Lomas de Zamora suburb of Buenos Aires, three policemen (First Sergeant Nicolás Cardozo, Corporal Roberto Roque Fredes and Constables Eugenio Rodriguez and Abel Pascuzzi) were killed after their patrol car came under fire from Montoneros guerrillas.

[88] On 5 March 1975, a Montoneros bomb detonated in the underground parking at Plaza Colón of the Argentine Army High Command; a garbage truck driver (Alberto Blas García) was killed and 28 others were wounded,[89] including four colonels and 18 other ranks.

[90] In early June 1975, Montoneros guerrillas murdered executives David Bargut and Raúl Amelong of the Acindar steel firm in Rosario, in reprisal for alleged repression against striking employees.

"[114] In January 1976, the son of retired Lieutenant-General Julio Alsogoray, Juan Alsogaray (El Hippie), copied from his father's safe a draft of "Battle Order 24 March" and passed it to the head of the Montoneros intelligence, Rodolfo Walsh, who informed the guerrilla leadership of the planned military coup.

[115] Private Sergio Tarnopolsky, serving in the Argentine Marine Corps in 1976, also passed on valuable information to Walsh regarding the tortures and killings of left-wing guerrillas taking place in ESMA.

On 26 January, urban guerrillas operating in the suburb of Barracas in Buenos Aires, shot a female police traffic officer (21-year-old Silvia Ester Rosboch de Campana) twice in her stomach around 7 AM as she left her place of residence that was Tomás Liberti 1145 for work.

[124] On 21 June, the labour relations manager of Swift (an American food processing company), Osvaldo Raúl Trinidad was shot and killed outside his home in the La Plata suburb of Buenos Aires after coming under fire from a carload of masked Peronist gunmen.

[129] On 26 July, Montoneros guerrillas operating in the San Justo suburb of Buenos Aires shot and killed an off-duty policeman, Ramón Emilio Reno in the presence of his 13-year-old brother while they stood looking at a magazine stand.

[133] On 12 September 1976, a Montoneros car bomb destroyed a bus carrying police officers in Rosario, killing nine policemen[134] and a married couple, 56-year-old Oscar Walter Ledesma and 42-year-old Irene Ángela Dib.

[126] On 29 December, urban guerrillas shot and killed Colonel Francisco Castellanos and wounded his driver, Private Alberto Gutiérrez, just a few blocks from the army officer's home in the suburb of Florida in Buenos Aires.

Justice Minister Ricardo Gil Lavedra, who formed part of the 1985 tribunal judging the military crimes committed during the Dirty War would later go on record saying that "I sincerely believe that the majority of the victims of the illegal repression were guerrilla militants".

[153] On 11 August 1976, urban guerrillas dressed like police officers intercepted and killed army corporal Jorge Antonio Bulacio, with two shots to the head and set fire to his military lorry belonging to the 141st Headquarters Communications Battalion with a Molotov cocktail bomb.

[155] On 4 January 1977, a female guerrilla (Ana María González) from the Montoneros movement shot and killed Private Guillermo Félix Dimitri of the 10th Mechanized Infantry Brigade while he was on roadblock duty outside the Chrysler factory in the San Justo suburb of Buenos Aires.

[156] On 27 January, a Montoneros bomb explodes outside a police station in the city of Rosario in Santa Fe Province, killing a policeman (Miguel Angel Bracamonte) and a 15-year-old girl (María Leonor Berardi), an innocent bystander.

[157] On 28 January, a female Montoneros guerrilla (22-year-old Juana Silvia Charura) placed a bomb inside the 2nd Police Station in the suburb of Cuidadela, destroying the building and killing three policemen: Commissioner Carlos A. Benítez, Sub-Commissioner Lorenzo Bonnani and Agent César Landeria.

[159] On 17 February 1977 around 06.30 local time, Ireneo Garnica and Alejandro Díaz, both railway workers who had refused to participate in a strike, were killed when Montoneros threw a bomb at them from a car in the suburb of Quilmes in Buenos Aires.

The seven MPM guerrillas involved, including two women, ambushed the 55-year-old French national in the suburb of Ranelagh after using a truck to block his route before spraying his car with a hail of submachinegun fire before making good their escape.

According to Montoneros, Peronism can be reformed by simply "correcting the reason" of Isabel Perón and José López Rega and committing to a platform centred around labour corporatism, Catholic socialism and anti-imperialism.