Martyrdom of Saint Peter. The Crucifixion of Saint Peter is a work by Michelangelo Merisi da Caravaggio, painted in 1601 for the Cerasi Chapel of Santa Maria del Popolo in Rome.
   Across the chapel is a second Caravaggio work depicting the Conversion of Saint Paul on the Road to Damascus. On the altar between the two is the Assumption of the Virgin Mary by Annibale Carracci.
   The two lateral paintings were commissioned in September 1600 by Monsignor Tiberio Cerasi, Treasurer-General to Pope Clement VIII who purchased the chapel from the Augustinian friars on 8 July 1600 and commissioned Carlo Maderno to rebuild the small edifice in Baroque style. The contract for the altarpiece with Carracci has not been preserved but it is generally assumed that the document had been signed somewhat earlier, and Caravaggio had to take into consideration the other artist's work and the overall iconographic programme of the chapel.
   Cerasi nourished a deep devotion towards Saint Peter and Paul, and invoked them in his will. Together the two saints represented the foundation of the Catholic Church, and they were called the Princes of the Apostles.
   Both had a strong connection to the city of Rome and the papacy. Caravaggio's paintings were thus intended to express Cerasi's attachment to the Church of Rome and his closeness to papal power. Their position in the chapel was important but the devotional focus was still on the Assu
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