Fifty-two people died before Iraq's Counter-Terrorism Service stormed the church with the support of U.S. forces.
The attack at the Cathedral of Our Lady of Salvation remains one of the single deadliest assaults against Christians in Iraq since the start of the war in 2003.
Already in 2010, four years before the invasion of Iraq by the Islamic State, almost half of the beleaguered Christian population had already fled the war's sectarian violence and persecution.
The beatification causes of the 48 Catholics who died inside the Cathedral of Our Lady of Salvation in 2010 advanced from the diocesan phase to the Vatican in October 2019.
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When the cathedral was restored after the attack, a red carpet was placed down the center aisle in memory of the blood shed at the site.
In his speech in the cathedral on March 5, Pope Francis recalled the men and women who died in the attack over 10 years ago.
"We are gathered in this Cathedral of Our Lady of Salvation, hallowed by the blood of our brothers and sisters who here paid the ultimate price of their fidelity to the Lord and his Church," he said.
"May the memory of their sacrifice inspire us to renew our own trust in the power of the cross and its saving message of forgiveness, reconciliation and rebirth."
Remembering all victims of violence and persecution, regardless of religion, he said that the deaths of the 48 Servants of God killed in 2010 were "a powerful reminder that inciting war, hateful attitudes, violence or the shedding of blood are incompatible with authentic religious teachings."
"For Christians are called to bear witness to the love of Christ in every time and place," he continued. "This is the Gospel that must be proclaimed and embodied in this beloved country as well."

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Pope Francis encouraged Iraqi clerics, religious, and lay leaders in the "daunting pastoral challenges" they faced daily.
"All of you share in the joys and sufferings, the hopes and anxieties of Christ's faithful," he said.
Despite the additional difficulties caused by the pandemic, he said that what "must never be locked down or reduced, however, is our apostolic zeal, drawn in your case from ancient roots, from the unbroken presence of the Church in these lands since earliest times."
"Hardships are part of the daily experience of the Iraqi faithful," the pope acknowledged. "In recent decades, you and your fellow citizens have had to deal with the effects of war and persecution, the fragility of basic infrastructures and the ongoing struggle for economic and personal security that has frequently led to internal displacements and the migration of many people, including Christians, to other parts of the world."
He thanked the priests and bishops for being close to their people and being peacemakers.
"The educational and charitable apostolates of your local Churches represent a rich resource for the life of both the ecclesial community and the larger society," he said. "I encourage you to persevere in these efforts, in order to ensure that Iraq's Catholic community, though small like a mustard seed, continues to enrich the life of society as a whole."