It was a Mass celebrated in St. Peter's Basilica, but it made international news.
Walking side by side with the superior of the Armenian Church and with the Patriarch, the Pope described the massacre of more than one million Armenians as a genocide.
"It is widely considered 'the first genocide of the 20th century.' It struck your own Armenian people, the first Christian nation.”
Whether or not the Pope would actually use the word 'genocide' had triggered wide spread speculation.
From 1915 to 1923 about 1.5 million Armenians were killed under the Ottoman empire in what is now present day Turkey.
Armenians applauded the Pope's remarks. Turkey which has long denied the genocide, arguing they were casualties of war- disapproved. The Pope said, acceptance is part of the healing process.
"Concealing or denying evil is like allowing a wound to keep bleeding without bandaging it.”
The Pope also linked the Armenian genocide to the current persecution of Christians.
"On account of their faith in Christ or their ethnic origin they are publicly and ruthlessly put to death, decapitated, crucified, burned alive or forced to leave their homeland.”
Armenia's president attended the Mass, along with other high ranking civil and religious authorities. Shortly after the Mass, Turkey summoned the Vatican's Ambassador and his counterpart in Rome to show their disapproval.
During the two hour Mass which followed the Armenian rite, the Pope also declared St. Gregory of Narek as a Doctor of the Church.