John and Marcianus, were Roman

Ancient Rome

Ancient Rome was a thriving civilization that grew on the Italian Peninsula as early as the 8th century BC. Located along the Mediterranean Sea and centered on the city of Rome, it expanded to one of the largest empires in the ancient world....

 martyrs. Marcianus was a Roman Senator, whose son John died of unknown causes. Sts. Abundius and Abundantius

Abundius and Abundantius

Abundius and Abundantius are Christian martyrs who were killed during the Diocletian persecution. Their feast day is celebrated on September 16.-Biography:...

, who were Christians condemned to execution, met Marcianus with his dead son on the way to their death. Abundius prayed over John, and he came back to life. At that moment, John and Marcianus both converted to Christianity

Christianity

Christianity is a monotheistic religion based on the life and teachings of Jesus as presented in canonical gospels and other New Testament writings...

. They too were martyred along with Sts. Abundius and Abundantius

Abundius and Abundantius

Abundius and Abundantius are Christian martyrs who were killed during the Diocletian persecution. Their feast day is celebrated on September 16.-Biography:...

, just north of Rome

Rome

Rome is the capital of Italy and the country's largest and most populated city and comune, with over 2.7 million residents in . The city is located in the central-western portion of the Italian Peninsula, on the Tiber River within the Lazio region of Italy.Rome's history spans two and a half...

, being beheaded ca. 304. The remains of Marcianus and John were found in 1001 and transferred to Civita Castellana

Civita Castellana

Civita Castellana is a town and comune in the province of Viterbo, 65 km north of Rome.Mount Soracte lies about 10 km to the south-east.-History:...

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Marcianus is one of the 140 Colonnade saints which adorn St. Peter's Square.