[2] Castro immediately appointed several military officers in various ministries,[2] dissolved the National Assembly, and ran the government as a dictator.

[citation needed] On the morning of May 14, a group of revolutionaries that included naval marines, army soldiers, some men from the Fiscal Guard (Portuguese: Guarda Fiscal), the National Republican Guard (Portuguese: Guarda Nacional Republicana) and accompanied by members of the Carbonária occupied the Naval Arsenal, in Lisbon, immediately taking possession of the arms.

Yet, Álvaro de Castro was fearful that loyal government troops in Lisbon would counter-attack and traveled to Santarém in order to shore up republican forces.

During subsequent hours on May 14, members of Pimenta de Castro's government escaped to the protection of the barracks in the Largo do Carmo, due to the disproportionate forces that were armed against them, and by the end of the afternoon had surrendered.

Between May 14 and 17 there was no existing law in the streets of Lisbon, allowing the members of the Carbonária and Formiga Branca to pillage, assassinate and conduct political retributions on their enemies; more than 20 police officers and officer cadets were summarily executed in the streets, police stations were attacked, private homes assaulted and clubs whose proprietors supported Pimenta de Castro were vandalized.

[6] Some Republican vigilantes proceeded to attack the newspapers that supported Pimenta de Castro, the monarchist's papers, and Machado Santo's O Intransigente.

[3] The revolt was victorious in substituting the unpopular dictatorship of Castro, for a Constitutional Junta in 1915, and forcing the resignation of Manuel de Arriaga.

With order restored Teófilo Braga became President and the Democratic Party leader, João Chagas, was nominated to head the government, but was unable to take-up his position, as he was in the hospital from the injuries sustained during the revolt.