On 12 August 1944, a crop combine was set on fire at Fornace Marchesini on the road to San Marino, a resistance gesture to prevent the Nazis from stealing grain. This event triggered the wrath of the fascist and Nazi troops, who went on a manhunt; a death sentence was passed on the resisters if they were caught. Two days later, on 14 August in the old barracks in Via Ducale, near the Tiberius Bridge, the three partisans were detained. The detainees were taken to German headquarters and tortured to get the names of their comrades: none of the three confessed.

On the day of mid-August, a mock trial was staged against the three and they were sentenced to death by hanging. The sentence was enforced the next morning in Rimini's main square. During the night before the murder, the three resisters were detained at the Convento delle Grazie, where the three wrote their last letters to their families with the comfort of the monks. At sunrise, the three were taken to Piazza Giulio Cesare, a square where they were hanged by the so-called 'Mongols', Turkmen auxiliary soldiers. Before dying, all three shouted 'Long live Stalin'. Their corpses were displayed as a warning to the citizens for three days before being buried in the municipal cemetery.

On 9 October 1944, the square was named after the Three Martyrs. The Cln (National Liberation Committee) and the fledgling administration's aim was to convey a clear signal to the population that this dedication marked the transition from the Fascist period to the Republic. Piazza Tre Martiri today symbolises the place of democracy and freedom for the Adriatic town.