This is Why & How Venice was built in a Lagoon!

One of the most memorable cities I have ever been to is Venice. The location in the middle of a Lagoon alone makes that city special.

But why was Venice built inside a Lagoon? Why did the original inhabitants go through all the troubles of erecting a city exactly here, in the middle of the water when the mainland of Italy was not even 2.5 miles away.

What were the reasons that outweighed the disadvantages such a remote location had?

Venice was built by Italian refugees fleeing the invasions of Germanic tribes during the 5th century. The small islands in the middle of the Lagoon offered perfect protection against raiders but quickly became too small for the number of refugees. So more than 10 million logs were rammed into the lagoon, limestone foundations were put on top of them, and Venice was expanded off the islands into the Lagoon.

Let`s find out more.

Events leading up to the formation of Venice

The formation of Venice is closely connected to the decline of the Western Roman Empire and its position in North-Eastern Italy. While the Alps protected most of Italy from invasions, there was a corridor between the alps and the Adriatic sea in north-eastern Italy allowing Germanic tribes to march into the area of the modern-day Italian province of Veneto.

The first roman settlements close to the region of Veneto were established after a roman campaign in 284 BC that was caused by an attack of the Gaul tribe of the Senones on Rome, more on that here.

In the second half of the first century BC, Veneto and the rest of the province of Cisalpine Gaul were dissolved and integrated into the ager Romanus.

Between the end of the roman republic and the invasions of the Germanic tribes of the Quadi and Marcomanni in 166 AD, the region of Veneto was peaceful and prosperous.

That changed with the decline of the Western Roman Empire.

Why was Venice built in a Lagoon?

In order to find out what changed in Italy that the foundation of a city in the middle of a Lagoon became reasonable, we have to take a brief look at the decline of the Western Roman Empire.

Effects of the fall of the Western Roman Empire on Northern Italy

Although there were the already mentioned invasions of the Marcomanni and Quadi in 166 AD the military of the Roman Empire was mostly able to keep invaders away from the Roman territory.

That changed when the power of Rome declined. That decline of roman power had several reasons. But these reasons are a story for another time.

After the final separation of the Roman empire into the Eastern Roman Empire with its capital Constantinople and the Western Roman Empire with its capital Rome in 395 AD, the latter had tremendous difficulties fighting off invading tribes.

Especially during the migration period, several Germanic tribes (which in return were repressed by the Huns) pressed into the former territory of the Western Roman Empire. Once again the already mentioned corridor between the Alps and the Adriatic sea was a more comfortable entry into Italy than having to march across the Alps.

And that brings us to the early days of Venice.

The foundation of Venice

With different Germanic tribes crossing and plundering the region of Veneto a wave of Refugees was looking for security. And some of the refugees who were forced to leave their cities and villages turned towards the Adriatic sea where they would find a shallow Lagoon.

Within the Lagoon of Venice, there were around 118 thinly populated small islands. Their location made these islands easy to defend against a force that was fighting on horseback or foot but did not have boats!

During the early 5th century AD inhabitants of the region of Veneto decided to settle the islands of Torcello, Jesolo, and Malamocco in fear of future invasions. And on March 25th 421 AD the city of Venice was officially founded.

Over the next years, more and more inhabitants of mainland Northern Italy settled in Venice. Especially after the Huns under their leader Attila had demanded the Western Roman Emperor Honorius to give them the official permission to settle in Veneto (not that Honorius would have been able to drive them out).

The thought of a permanent presence of the Huns encouraged many of the mainland inhabitants to move to Venice where they would be safe from the Huns.

Venice is expanded of the islands into the Lagoon

With more and more refugees leaving their homes on the Italian mainland the original islands of Venice quickly became too small. New space had to be created. Luckily the original islands inside of the Lagoon were relatively close together so canals were dug and the sides were propped up with logs that were rammed into the sludgy ground of the Lagoon.

It was in these early days that Venice already had to start trading. The problem was that the city needed a lot of logs to build the foundations of the parts of the city that were outside of the original islands.

Digression: How was Venice built on the Water?

Since there was not enough wood available in Italy logs were imported from modern-day Croatia and Slovenia.

More than 10 million logs, most of them imported, were rammed into the muddy ground of the Lagoon. On top of these pillars, plates of Limestone were placed to expand the surfaces of the natural small islands. Streets and buildings were then constructed on top. Until this day many of the logs holding up the city are still originals.

Now one might question how logs could persevere for more than 1500 years without rotting away. The answer is simple.

First of all, the logs that make up the foundation of Venice are completely covered by the saltwater of the Lagoon keeping away oxygen from the wood. And the wood that was chosen to uphold the foundations of Venice was alder which is resistant to rotting away. The fine clay sediments of the Lagoon also did their part by over time transforming the logs into a material with the consistency of stone.

Today the city of Venice has more than 400 bridges spanning over canals and connecting the countless small and artificially enlarged islands. And just like during the time of its foundation in the 5th century AD boats are still the only mode of transportation.

But let`s return to why Venice was built in a Lagoon and which advantages that position had not only during the migration period of the 5h century but also centuries later.

It is important to state that Venice was not independent yet!

Venice as a Byzantine outpost

After the year 540 AD Venice was the most western outpost of the byzantine empire and officially ruled by a Byzantine governor who was residing in Ravenna from where he would rule over the byzantine possessions in Italy. After 697 AD Venice would be ruled by a doge, the first one being Paolo Lucio Anafesto.

By the way, the doges would reside in the Doge`s Palace. When you visit Venice (or watch the video below, following minute 1:00 ) you will also see the Piazza San Marco with its iconic bell tower, the San Marco Basilica, and the doge`s palace.

In 751 AD Ravanna was conquered by the Lombards but the position of Venice in the Lagoon protected the city from being conquered itself. While officially still the byzantine outpost that was the furthest west, Byzanz had no more control over Venice.

The conquests of the Lombards did not only drive another wave of refugees to Venice increasing its population but also started the golden era of Venice!

The Golden era of Venice

From the 8th century on Venice started developing into a so-called thalassocracy that was governed by the doge and several supervising committees. A thalassocracy is are seaborn empire with only limited rule over settlements on the land. Examples are Venice, Amalfi, Pisa, and Genoa.

Venice would soon start to clean the Adriatic sea of pirates and establish outposts all along the Adriatic coastline. In the 10th century, Venice had developed into an important trading and naval power

During the 11th century, Venice had become the dominant naval power within the Mediterranean controlling not only the spice trade but also owning a far stretched system of tradeposts from the Adriatic sea to Cyprus and the Crimea.

And in the 13th century, a Venetian fleet was responsible for transporting crusaders to the Holy land and conquering the at that point still Christian city of Constantinople in 1204. At that point in time, the trade routes of Venice stretched all over the eastern Mediterranean.

Until the 15th century, Venice would stay a global trading center with a remarkable production of glass, more on that here, but also for shipbuilding. During the height of Venice’s power, the shipbuilders could build and equip one warship per day!

The decline of Venice

Since Venice basically had a monopoly on the spice trade and controlled the eastern Mediterranean other naval powers like Spain and Portugal were forced to look for another way to get to India and its spices.

Spain and Portugal both chose to try to circumnavigate the African continent to get to India. But one sailor had a different idea and wanted to sail west to find a new route to India.

That man was Christopher Columbus who while trying to find a new sea route to India would discover the New World by accident. That would lead to colonies being set up in the New World and to a westward shift of attention. As a result of Columbus`s discovery, the Mediterranean (and Venice) lost their significance in trade.

The discovery of Christopher Columbus would also open up a new trade route. But that triangular trade is a story for another time. More on that here.

Why is Venice called Venice?

Venice was one of the rare Italian settlements that were not founded or settled by the Romans. The city of Venice got its name from the Italian region of Veneto on which shores the Lagoon of Venice lies and was officially founded on March 25th 421.

Impressions of Venice

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Venice was built by northern Italian refugees fleeing the invasions of Germanic tribes during the 5th century. The small islands in the middle of the Lagoon offered perfect protection but since more and more refugees arrived these natural islands became too small. So they were artificially enlarged by ramming logs into the ground of the Lagoon. These logs and the limestone plates that were put onto them made up the foundation of the expanding city of Venice.

I hope you enjoyed our trip to Northern Italy as much as I did.

Take care of yourself because you deserve it. You really do.

Until next time

Yours truly

Luke Reitzer


M. Maier: Geschichte der Völkerwanderung. Europa, Asien und Afrika vom 3. Bis zum 8. Jahrhundert n. Chr. (München 2019).