But in a statement released shortly after the ceremony, Mr. Macron’s office fell short of doing so, instead holding only the Paris police responsible and refraining from calling the killings a massacre.
“The crimes committed that night under the authority of Maurice Papon are inexcusable for the Republic,” the statement read, referring to the Paris police chief who ordered the suppression of the protest.
Mr. Macron’s presence at the commemorations comes against a tense political backdrop in the prelude to next year’s presidential election: The country’s colonial past in Algeria is a trauma that continues to haunt and shape France, with nostalgia on the right and resentment among the country’s large Muslim population.
And they are taking place amid diplomatic tensions between France and Algeria. The Algerian government recently recalled its ambassador after Mr. Macron questioned the existence of an Algerian nation before French colonization and accused Algerian leaders of “rewriting” their country’s history based on a “hatred of France.”
It was during Algeria’s war of independence on the other side of the Mediterranean that the police killings of the Paris protesters took place.
On Oct. 17, 1961, as the eight-year conflict was nearing its end, Algerian National Liberation Front independence fighters called on Algerians in Paris to organize a peaceful march to protest a nightly curfew that was being imposed on them after a spate of deadly attacks on French police officers.
About 20,000 to 30,000 people turned up, and the police crushed the march before it could even begin. They arrested 12,000 protesters, beat some to death, and shot or threw others into the Seine River, where they drowned.
For several weeks, unidentified corpses were found along the river banks.
In addition to the dozens killed that night, many others fell victim to police raids and violence that had begun that September and continued for several days after the scheduled protests. Over that period, historians estimate, the total death toll was 100 to 200 people.
Fabrice Riceputi, a historian of the Algerian War who has written about the killings, described the events of Oct. 17 as “a peak in a period of state terror that is inflicted on the colonized people.”
But for decades the French state maintained that the official death toll was just three.
It was only in the 1990s, after the groundbreaking work of the French historian Jean-Luc Einaudi, that the extent of the police’s actions began to be uncovered. His findings were made public as part of a trial in which it was also brought to light that Mr. Papon, the police chief, had participated in the deportation of more than 1,600 Jews during World War II.
“From the start, the government imposed silence,” Mr. Riceputi said, adding that it had blocked calls for the creation of a parliamentary commission to investigate the killings, civil cases filed by Algerians seeking justice and access to key archival documents.
But the silence was also more widespread: The French news media largely ignored the events, as did the country’s left-wing political opposition and the government of the newly independent Algeria.
The statement from Mr. Macron’s office on Saturday acknowledged as much. “This tragedy was long kept silent, denied or concealed,” it read, describing the killings as “brutal, violent and bloody.”
Since becoming president in 2017, Mr. Macron has sought to heal the memories related to the French colonization in Algeria and address the lingering effects of the Algerian War.
But recognizing the role of the police in the 1961 massacre also risks stirring volatile debates about police violence and racism in France. High-profile cases of officers’ behavior such as beating a Black radio producer and carrying out discriminatory police checks in recent years have set off outrage and widespread protests.
The timing of Saturday’s commemoration, coming in the year before a presidential election, was also a factor for Mr. Macron. France’s current political climate is dominated by issues of security and cultural identity, and Mr. Macron has tried to appeal to conservative voters who have often balked at making amends for the nation’s colonial past.
In January, his office said that there would be “neither remorse nor apologies” for France’s occupation of Algeria.
And last month he asked for “forgiveness” for the abandonment of Harkis, Algerians who fought for France during the war and have often shown strong support for Marine Le Pen, the leader of France’s far right, who is a strong challenger to Mr. Macron in the election.
At Saturday’s ceremony, Mr. Macron observed a minute of silence and laid a wreath near the Seine where police officers in 1961 threw in several protesters.