The symbolic revolt of 18 soldiers in 1922 had a lasting impact on Brazilian politics, and contributed to the downfall of the Old Republic in 1930. The incident started when Govenor of Minas, Artur Bernandes, was proposed as a presidential candidate by the São Paulo-Minas League. In order to lessen his favour among the army, fake letters were leaked to a Rio newspaper, causing serious offense amongst military officers. Despite this dirty trick, of which he was eventually absolved, Bernades went on to win the election. The government then tried to use troops for political purposes in Pernambuco, overriding army policy of avoiding partisan conflicts. The effect of these two incidients was to create a high degree of tension between the government and the army, particularly Leiutenants. These officers were perhaps additionally emboldened by the end of the First World War, and their behaviour can be seen as indicative of a wider trend in middle-class political activism.
The Lieutenants organised a revolt, supposedly timed to occur simultaneously in several bases. However, the Republican government heard rumors that the army was on the verge of revolt, and pre-emptively shut several bases. One army base, Forte de Copacabana, remained in the hands of the revolutionaries. The government told the men surrender or die. After letting the enlisted men leave, the remaining 18 Lieutenants, each carrying a piece of the Brazilian flag, left their stronghold at the Copacabana Fort, and marched towards Catete Palace. They were intent on making their demands for social and political reform heard by the Executive Power, at any cost. Blocking their path were 3000 republican troops. By the end of the day, only two Lieutenants were left standing.
The Old Republic, which was dominated by members of the old coffee growing families, congratulated themselves on having quelled the rebellion. But the legend of the Lieutenants did not fade into history, and when Getulio Vargas finally overthrew the Old Republic in 1930, the ‘revolt of the 18’ was cited as a landmark event.