Torcello is said to have been named for the tower in Altinum where the bishop was vouchsafed his vision, when he was seeking refuge for his flock from the savage, heretic Lombards. The idea of height seems essential to this tiny island, which must have figured in its own eyes as a lighthouse of faith and a lookout-point for dangers. The flight of the faithful took place in 638, though in fact some earlier settlers had fled here from Attila in 452. Nothing remains of this first settlement, which may have been impermanent. But Bishop Paul took his see with him from ravaged Altinum, and the Cathedral to S. Maria Assunta (again the idea of height) was erected the next year, in 639. It was modified twice, finally in 1008, but it kept its original form, that of the Ravenna churches, and, standing in tall grass, it still diffuses the early-Christian aura of the Exarchate, of Ravenna's San Vitale and Sant' Apollinare in Classe, which once too looked over a harbor, now silted in and covered with that lonely pine forest where Dante and Byron poeticized and Garibaldi hid.
No building in Venice is as old as this. St. Mark's, in the Ravenna style, was begun in 829, but it was twice destroyed, burned down once by the people in rebellion against a tyrannous doge, restored, and torn down again by an eleventh-century doge who wanted his chapel in the fashionable Byzantine style. (It was his successor, Doge Selvo, that married the Greek wife.) The present St. Mark's, in the shape of a Greek cross with five domes and modeled, some think, on the church of the Twelve Apostles in Constantinople, is the result of his initiative. The Venetian passion for building had its destructive side. When the Doge's Palace was partly destroyed by fire in the sixteenth century, a commission of architects was consulted, and Palladio counseled tearing down what was left and building a new one. If it had not been for the counter-advice of the Florentine Sansovino, who was more of a trimmer, the Doge's Palace today would be in the Palladian style and a wonder of the world would be lost. The church of San Geminiano (whose destruction brought down the pope's interdict) was repeatedly torn down; its position in St. Mark's Square was unlucky for it. Sansovino's San Geminiano, the last of its line, was demolished by Napoleon to create the Fabbrica Nuova, where the Correr Museum is now located.
The pope had some reason to be angry, for the old church was believed to go back to the sixth century, to Narses the Eunuch who ruled Italy from Ravenna for the Emperor Justinian and had made use of Venetian transport for his armies in his campaign against the Goths. He was one of the first foreigners to be struck by Venetian prosperity. According to tradition, Narses built two churches on what is now the Piazza in fulfilment of a vow: San Geminiano, which he ornamented with marble columns and precious stones, and the more modest church of St. Theodore, later swallowed up by St. Mark's, like its patron and his crocodile. A still earlier church, San Jacopo di Rialto, is supposed to have been put up on the site of a shipyard in the fifth century. But the present San Giacometto di Rialto (open one day a year), which claims to be that church, is really an eleventh or twelfth century creation, much restored and rebuilt, the last time in the seventeenth century.