Pope John XV was the bishop of Rome and ruler of the Papal States from August 985 until his death. A Roman by birth, he was the first pope who canonized a saint. The origins of the investiture controversy stem from John XV's pontificate, when the dispute about the deposition of Archbishop Arnulf of Reims soured the relationship between the Capetian kings of France and the Holy See.
Pope John XV is mentioned in the Dagome iudex, one of the earliest written records of the nation of Poland.
Canonization is the declaration of a deceased person as an officially recognized saint, specifically, the official act of a Christian communion declaring a person worthy of public veneration and entering their name in the canon catalogue of saints, or authorized list of that communion's recognized saints.
Canonization of Elizabeth of Hungary in 1235. Sándor Liezen-Mayer (1863).
Pope Pius II canonizes Catherine of Siena.
The Turkish atrocities in Bulgaria (1876). On 3 April 2011, Batak massacre victims were canonized as saints.
On 4 November 1992, the Holy Synod of the Church of Greece unanimously declared saints those Christians who had been tortured and massacred by the Turks in the Great fire of Smyrna in 1922.