Napalpí was not a free village. It was one of several Indigenous reductions established to control the region's native peoples, settlements that functioned in practice as forced-labor camps. The Qom and Moqoit who lived there were compelled to work the cotton fields under harsh and exploitative conditions, their movement and their wages controlled by others. In the weeks before the massacre, faced with abuses they could no longer accept, the workers refused to harvest. That refusal was answered with bullets. As the Toba chief Esteban Moreno recounted in a memory carried down through generations, an aircraft circled overhead as the shooting began. They were killed, he said, because they would not harvest. The place came to be called, in sorrow, the Colony of the Massacre.

The accounts that survive are difficult to read, and they should be. A contemporary newspaper, the Heraldo del Norte, described how, around nine in the morning and without a single shot fired by the people gathered there, the police fired repeatedly at close range, sparing neither women nor children nor the wounded. Forty days later, Enrique Lynch Arribálzaga, the former director of the Napalpí compound, wrote a letter read aloud in the National Congress: the killing was continuing, he warned, as though someone wished to erase every witness before an investigation could be held. The dead were buried in mass graves; some bodies were burned. These were not casualties of a battle. Not one of the attackers was harmed, because, as Moreno insisted, it was never a fight at all.

Memory outlasted the silence. Among the survivors was Rosa Grillo, born in February 1908, a child when the shooting came and an old woman by the time the country was willing to listen. She lived to 115, dying on 4 April 2023, the last known survivor of that morning. For the decades in between, the testimony of people like her, and of the descendants who kept the story alive, was nearly all that stood against official forgetting. The state had records and reports it chose to bury; the Qom and Moqoit had grandmothers who remembered. That so much of the truth survived at all is owed to communities that refused to let their dead be written out of history.

Justice, when it came, could not punish anyone, because everyone responsible was long dead. So Argentina pursued a different kind of reckoning. In 2019, a federal court formally recognized the massacre as a crime against humanity, placing it beyond any statute of limitations. Three years later, in 2022, the country opened a truth trial — a proceeding meant not to convict individuals but to establish, formally and permanently, what had occurred and who bore responsibility. On 19 May 2022, Federal Judge Zunilda Niremperger ruled that the Argentine state bore responsibility for the massacre, organized under Governor Fernando Centeno to exterminate the Qom and Moqoit communities. The judge read her ruling aloud simultaneously in the Qom and Moqoit languages. The court ordered that the events be taught in schools and that a day of national commemoration be considered. As the human rights official Horacio Pietragalla Corti put it, the trial was meant to build, through justice, a truth set down in writing, one that might offer some symbolic repair to the families of the victims. The cemetery that gave Napalpí its name was, at last, acknowledged as such.