Evaristus succeeded Clement I as Bishop of Rome around AD 99 and governed the small Roman Christian community during the difficult final years of Trajan's reign. The Liber Pontificalis (the early-medieval book of papal biographies) attributes to him the institutional structural decision of dividing the city of Rome into territorial parishes assigned to specific presbyters — the foundational moment of the Catholic territorial parish system, though the historical reliability of this 6th-century source for the late 1st-century papal administration is debated.
He is traditionally identified as a martyr — the early papal lists include him in the cluster of early popes presumed to have died as martyrs during the Trajanic and Hadrianic period, though the specific circumstances of his death are not recorded by contemporary sources. He is buried near the tomb of St. Peter at the Vatican.