In the late 560s, a Germanic group known as the Lombards was wrecking havoc through northern Italy.
To escape the invaders, boatloads of people fled into the Venetian lagoon, a morass of swampy mudflats and scattered islands.
Formed over centuries by the outflow of silt from the Po and Piave rivers and the counterforce of Adriatic currents, this marshy maze was constantly shifting and disappearing.
These qualities made it both the perfect spot to hide and a very unstable place to live.
So the new arrivals set out to tame the lagoon and build the most unlikely of cities from the mud.
While some fishermen already inhabited the region in stilted huts, the settlers wanted to build a foundation to support heavier, longer-lasting structures.
Little did they know their work would support Venice to this very day.
They drove clusters of one to three meter long wooden piles into the ground in a process that squeezed out groundwater and compacted mud around the piles.
This created an oxygen-free environment that protected the wood from insects and fungi.
The piles were still vulnerable to minor bacterial damage, but otherwise impervious to rot.
And this sealed system of wood, water and mud is still supporting Venice 1,500 years later.
Wooden beams and stone platforms above the piles provided the basis for buildings and sometime around 697, the settlers formally declared their new home the Republic of Venice.
Initially, footbridges were built to connect the islands, but these were prone to decay, collapse and fire.
Many, like the famed Rialto Bridge, had to be regularly rebuilt, each time incorporating new materials and techniques to improve their longevity.
By the 11th century, the channels between islands had been reinforced into stone-lined canals navigated by slender gondolas.
And unlike the rest of Europe, where nobles typically rode above commoners, the city's layout necessitated foot travel for all classes.
Yet despite this clever engineering, the Republic still had no land for farming, so Venetians were heavily dependent on trade.
Fortunately, Venice's location made it the perfect port city to connect markets from Europe to the Silk Road.
Its canal network allowed boats to dock close to warehouses, and the challenge of navigating its narrow waterways protected the city from outsiders.
These advantages helped make Venice a major maritime power, and the 1200s began with their biggest business deal yet.
The Pope brokered an arrangement with Venice's elected leader, Enrico Dandolo, to produce ships and arms for the Fourth Crusade's anticipated 33000 soldiers.
Dandolo agreed. investing huge amounts of the Republic's money and resources.
But when it was time to set sail, only one third of the soldiers arrived, with less than half of the promised payment.
Furious Dandolo redirected the crusading army against Venice's Christian rivals, including Constantinople.
This campaign laid the foundation for Venice's overseas empire, and over the following centuries, Venetian merchants like Marco Polo ventured as far as China.
During the Renaissance, the Republic became a hub of art and intellectual life.
Its sail-making looms were repurposed to create vast canvases.
Its craftsmen pioneered various printing techniques, and the silica-rich sands from the Ticino and Adige rivers fueled extravagant glassworks.
However, in addition to art, silks and spices, the Venetians also traded enslaved peoples to work in private homes or on ships.
Once freed, some stayed in the city, even finding work as gondoliers.
Venice's dominance over the Mediterranean remained unchallenged until the mid-15th century, when the Ottomans conquered Constantinople.
In the following centuries, the Ottomans used their navy to interfere with Venice's business, all while new transoceanic trade routes excluded Venetians.
The Republic soldiered on until French attacks forced it to dissolve in 1797, at which point Venice traded hands between Austria and France several times before finally being ceded to Italy in 1866.
No longer able to compete commercially, Venice was reinvented as a tourist destination.
But today, rising sea levels are threatening to sink the so-called floating city.
In 1900, the then 900-year-old Basilica di San Marco flooded about seven times a year.
Now it experiences roughly 250 annual floods.
And tourists are perhaps just as dangerous.
As millions of annual visitors speed along in motorboats, they erode the muddy barrier protecting Venice's foundations.
Left unaddressed, these modern advances could destroy one of the world's most remarkable cities.
Thank you.
