Speaking after a formal meeting with Paraguay's controversial President Horacio Cartes, the pope condemned the nation's "terrible sufferings brought on by war, fratricidal conflict, lack of freedom and contempt for human rights."
He may have been alluding to the War of the Triple Alliance, one of the deadliest in Latin American history, fought in the 19th century by Paraguay against the alliance of Brazil, Argentina and Uruguay; to this day it haunts Paraguay's national identity, and many here had hoped the pope would mention it.
"A people which forgets its own past, its history and its roots, has no future," the pope added. "Memory, if it is firmly based on justice and rejects hatred and all desire for revenge, makes the past a source of inspiration for the building of a future of serene coexistence. It also makes us realize the tragedy and pointlessness of war. Let there be an end to wars between brothers!
The pope's arrival in Asuncion followed prayers in Bolivia with the inmates at a notorious prison and, on Thursday, a heartfelt apology to indigenous groups for the colonial-era atrocities committed by the Catholic Church.
The pope was expected to continue pressing his favored themes of helping the poor and downtrodden. But in Paraguay, there are other challenges. Unlike Ecuador and Bolivia, this landlocked country is ruled by a conservative businessman. Cartes is less receptive to progressive social policies that the pope sometimes promotes.
Cartes' predecessor, Fernando Lugo, was a former Catholic priest who was ousted in an impeachment that some in South America described as nothing less than a coup by the party that traditionally ruled Paraguay until Lugo's election. Cartes returned to power the Colorado Party of the late dictator Alfredo Stroessner.
Although a recent survey by the Pew Research Center listed Paraguay as the most Catholic country in South America, with high Mass attendance, many here are disillusioned by issues such as recent clerical sex-abuse scandals. The pope will attempt to woo them back to the fold.
"I used to never miss Mass; I was really dedicated," said Anibal Recalde, a 50-year-old out-of-work mechanic hoping to catch a glimpse of the pope. "But all of what happened with the abuse of children made me lose faith in the church, and for the last four or five years I stopped going. That's what the pope wants to change and needs to change."
Recalde said he hoped the pope would tell Paraguay's leaders to care for the poor, "a message that has not arrived to Paraguay yet."
"This is our pope," said 10-year-old Jorge Espinola, his face caked with dirt as he sold Francis balloons at an intersection for $4. "I hope that he brings miracles here, because I know he can."
Rosario Bagodo, 25, was eating lunch before her shift selling empanadas at a gas station, for which she earns minimum wage equivalent to about $385 a month. "I hope the pope tells our government to pay more attention to education and healthcare," she said. "I don't go to Mass, I can't, because I work too much. But I pray."
Asuncion was spruced up for the pope's visit, with red, white and blue Paraguayan flags draped alongside the papal white and yellow.
People lined up along the streets, waiting for the popemobile to pass. Some wore shirts with sayings in the local Guarani language, such as "Messenger of joy and peace," the slogan of this leg of the pope's landmark visit to his native continent.
Earlier in the day in Bolivia, Francis visited one of Latin America's most violent prisons and urged inmates not to despair.
The notorious Palmasola prison holds murderers, drug traffickers, gang members and other criminals. Like most jails on the continent, many of those inside have never been convicted of anything; many inmates' families live there with them.
Bolivian officials say the Palmasola houses about 4,000; experts say the real number could be twice that. It was built for 800. There are at least 100 children living there, and authorities have little control over what goes on inside the prison.
The pope listened intently as three inmates described the nightmarish reality that they and thousands of others experience: not knowing how long one is going to be incarcerated; not having access to any sort of rehabilitation programs; exposed to violence and corruption; forced to sleep on floors. One prisoner even described witnessing a killing.
Francis expressed sympathy for their plight but told them not to give up hope or their personal dignity.
"Detention is part of a process of reintegration into society. I know that there are many things here that make it hard: overcrowding, justice delayed, a lack of training opportunities and rehabilitation policies, lack of access to studies, violence."
All of which augurs for institutional reforms, he said. "And yet, while working for this, we should not think that everything is lost."
A day earlier, he apologized for the colonial-era crimes committed "in the name of God" and demanded structural economic change to help the poor.
"I humbly ask forgiveness, not only for the offenses of the church herself, but also for crimes committed against the native peoples during the so-called conquest of America," he said.
Special correspondent Bevins reported from Asuncion and Times staff writer Wilkinson from Mexico City.