The ceremony, in Algeria's second city, Oran, was conducted by Italian Cardinal Angelo Becciu on behalf of Pope Francis.
During a service attended by 1,200 people, including pilgrims, relatives, and friends of the beatified, Becciu read the official decree stating that the 19 men and women would "from now on be called blessed."
In a message read during the ceremony by Becciu, Francis spoke of his hope that "this celebration helps to heal the wounds of the past and create a new dynamic of meeting and living together."
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"We believe that this unprecedented event in your country will draw a great sign of fraternity in the Algerian sky to the whole world," the pope wrote in a greeting.
The 19 Catholic clergy were killed between 1994 and 1996 as Algeria was in the grips of a decade-long civil war between government forces and Islamists that left up to 200,000 people dead.
Trappist monks among the blessedThose beatified included seven French Trappist monks, who were kidnapped from the Notre Dame de l'Atlas monastery in Tibhirine in 1996.
A radical group was blamed for their beheadings, but some observers have suggested Algeria's military was responsible.
Their deaths inspired a 2010 French film starring Lambert Wilson and Michael Lonsdale, Des Hommes et des Dieux (Of Gods and Men), that won the Grand Prix at the Cannes Film Festival.
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Others beatified included former Bishop of Oran Pierre Claverie, who was killed with his driver in 1996 when a remote-controlled bomb exploded at his residence. Eleven other religious men and women — from France, Spain, Belgium, and Malta, who were gunned down during the conflict — were also blessed.
The Church recognized all 19 as martyrs in January paving the way for the first event of its kind in a Muslim country.
The Algerian president allowed the ceremony despite continued tensions over the deaths.
Local Muslim dignitaries later on Saturday received the families of the slain clergy at the Ibn Badis Grand Mosque
mm/aw (AFP, AP, DPA)
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