AMFNB members, a welfare and trade union organization, were not armed and revolted to demand changes in the navy, counting on the mutual support of left-wing movements.

[a] In those two years it acquired thousands of members and a more combative leadership, coming closer to president Goulart and leftist organizations, as well as becoming interested in issues outside the navy, such as the base reforms [pt].

The CPSA, more numerous, recruited young men through volunteering, conscription and mainly through the Seaman Apprentice Schools, located in Pernambuco, Ceará, Bahia and Santa Catarina.

[12] The sailors lived in rented rooms, in groups, in poor neighborhoods (especially near the port area) or inside military units, especially on the ships, where the "chronics" or "barnacles" resided, as the on-board work required absolute availability.

[13][14] On the other hand, there was a romantic fascination with this adventurous life; for example, Avelino Capitani recalled the pride with which he was received when he returned to his hometown in Rio Grande do Sul's countryside, dressed in his sailor uniform.

[4] For one of them, Avelino Capitani, the conflict with the naval authorities originated in the perpetuation of the "old and archaic social command structure," while another, Antônio Duarte, did not believe in the navy's discourse, which exalted the institution's revolutionary transformation over time.

[30][31] This period, the first half of the 1960s, was a time of great mobilization in Brazil, with groups such as students, trade unionists, artists, organized peasants, communists, and the Catholic youth.

[45] The AMFNB published the newspaper A Tribuna do Mar and maintained representatives in the military organizations, the "delegates", responsible for spreading the institution’s message and collecting membership fees and contributions.

[48] This privilege was granted to less politicized class associations, but not to potential sources of problems like the AMFNB,[49] which was viewed with suspicion from the outset by the officers and investigated by the navy’s Intelligence Center (CENIMAR).

[55] At the time, he served at the Admiral Wandenkolk Instruction Center (CIAW), where numerous enlisted men attended specialization courses, making it a focal point for the AMFNB within the navy.

The exceptions were some officers aligned with the federal government of president João Goulart, such as Cândido Aragão, commander of the Marine Corps, who was himself a soldier who rose to the admiralty.

Aragão "provided vehicles for outings for apprentices newly arrived from the naval schools and allowed the association’s representatives to work freely in recruiting new members, in addition to serving as an intermediary between the Minister of the Navy and the AMFNB".

[61][62] In May 1963, the radicalizing speech of army sub-lieutenant Gelcy Rodrigues Correia — "we will take up our work instruments (rifles) and carry out the reforms together with the people" — resonated among the "fuzinautas".

According to Antônio Duarte, the election "boosted the soldiers' self-esteem and political confidence, confirming and strengthening the reformist view that transforming the conservative structure of the Armed Forces was possible".

Still, its activities would be monitored, as "its social body will always be temporary and composed of young men" and "will run the risk of falling into the hands of opportunists", "as has been happening in other sectors of Brazilian society".

In assemblies and demonstrations, the "fuzinautas" made demands such as "a revision of the Navy's Disciplinary Regulation, as well as better wages and working conditions, recognition of their association by the naval force, career stability, the right to vote and marry, and the permission to wear civilian clothes during off-duty hours".

[81] Tribuna do Mar reached a circulation of fifteen thousand copies, the leaders secured a program on Mayrink Veiga Radio, and on several occasions, they met with Darcy Ribeiro, the Chief of Staff to the Presidency of the Republic.

[82] President Goulart, Leonel Brizola, the General Workers' Command (CGT), and the Brazilian Communist Party (PCB) sought to leverage support from the AMFNB.

[88] Paulo Schilling noted how "the unity of the left had been restored": prominent figures from various sectors attended and gave speeches, including members of the Communist Party, the General Workers’ Command (CGT), Popular Action, and the Women’s League.

[93] "Cabo Anselmo", recognized for his oratory skills, delivered a highly political speech, touching on topics such as "landowners", "imperialism", "base reforms", and "the exploited".

Countering this accusation, he argued that those "trying to subvert order are the allies of hidden forces, which drove one president to suicide, another to resign, tried to prevent Jango's inauguration, and now block the implementation of the Base Reforms".

[115] In a note, the AMFNB defined the situation as "an epic that will culminate in reforms of our archaic regulations," while for the Navy, a "minority of the military, about 600 men, between sailors and marines, have been since last night in an attitude of frank indiscipline."

[127] The support was requested by the Navy Minister to the Ministry of War and included twelve tanks and 500 soldiers[125] of the Mechanized Reconnaissance Regiment and the 1st Army Police Battalion,[i] the latter with the field presence of Colonel Domingos Ventura.

[139][137] According to Hugo de Faria [pt], Goulart was actually thinking about amnesty, reasoning that it had been granted to officers involved in rebellions since 1922 and it would be unfair not to apply it to the enlisted men as well.

[141] For President Goulart, the result would prove negative, as the focus of political debate shifted from the reforms he advocated to military discipline, and his response to the revolt was considered tolerant of indiscipline.

[147] According to the columnist Carlos Castelo Branco, the left-wingers already compared what happened to "an action of the Kronstadt sailors in support of the Petrograd Soviet line", that is, to the Russian Revolution of 1917.

[156] The president felt supported by his military apparatus,[157] and the conquest of the legalists' camp was fundamental to the conspirators' victory: according to them, if Goulart had shown toughness with indiscipline, the correlation of forces would have been favorable to his permanence in power.

Another version, represented by political scientists Caio Navarro de Toledo and Alfred Stepan and historians Jacob Gorender [pt] and Nelson Werneck Sodré, treats the revolt carefully, distinguishes Anselmo from the AMFNB and writes little about the Association.

[179] The interpretation of the revolt as a destabilization blames Anselmo and puts credit on the testimony of naval officer Ivo Acioly Corseuil,[179] head of the Federal Service of Information and Counterintelligence [pt] (SFICI) in the Goulart government.

In a statement to Moniz Bandeira, published in 1977 in the book O governo João Goulart: as lutas sociais no Brasil (1961-1964), he stated that Anselmo was an agent of the Central Intelligence Agency (CIA) infiltrated into the sailors' movement to create a pretext for a right-wing coup.