Pope Mark succeeds Pope Sylvester I as the 34th pope of the Catholic Church. Pope Mark begins to build the basilica of San Marco; the church is devoted to St. Mark. The military successes of Emperor Constantine I result in most of Dacia being reconquered by the Roman Empire.
Geopolitics & Diplomacy
The military successes of Emperor Constantine I result in most of Dacia being reconquered by the Roman Empire.source
Religion & Belief
January 18 – Pope Mark succeeds Pope Sylvester I as the 34th pope of the Catholic Church.source
Pope Mark begins to build the basilica of San Marco; the church is devoted to St. Mark.source
Economy & Finance
The first recorded customs tariff is in use in Palmyra.source
Science & Discovery
December 25 – The first celebration of Christmas is recorded.source
Disasters & Accidents
Arius, Alexandrian priest, collapses in the street in Constantinople (approximate date).source