Venice’s history is inexorably linked with Constantinople, the ancient capital of the Byzantine Empire in the East, which became modern Istanbul in Turkey. A vast majority of the population was what we’d call Greek nowadays. After the famous 4th crusade in 1204, which was essentially an excuse for Venice to pilfer the most valuable treasures and booty from Constantinople, the Byzantine empire began to crumble and many Greeks emigrated west, especially to the prosperous Venice. And by the early 16th century, there were more than 4,000 orthodox Greeks in the city, who proudly preserved their language, religion and traditions; and so soon enough the Venetian state allowed them to build their own church: san Giorgio dei Greci which you see now. The belltower is quite obviously leaning to one side, and it is said it was built this way.
