326 CE

(traditional date) – Helena, mother of Constantine I, discovers the so-called True Cross and the Holy Sepulchre (Jesus's tomb) in Jerusalem. On her pilgrimage, which begins about this year, she pauses on the Aegean island of Patmos, where she is said to found the church of Panagia Ekatontapiliani. Emperor Constantine the Great travels to Rome to celebrate the 20th anniversary of his accession to power, but while en route at Pola he orders his older son, Crispus Caesar, to be executed, possibly on charges of adultery. Later, Fausta, second wife of Constantine I, is also executed by being suffocated or boiled in a hot bath. Helena tells Constantine that he must atone for executing his son and wife by building churches, and at about this date construction begins on Old St. Peter's Basilica, the first church on the traditional site of Saint Peter's tomb in Rome, and on the basilica of Golgotha on Calvary outside Jerusalem. He also commissions construction of the Church of the Nativity in Bethlehem (dedicated 339).