Runes in Hagia Sophia - a Viking trace in Istanbul
- Martin
- 9 hours ago
- 4 min read
Up in the gallery of Hagia Sophia, slightly away from where most visitors tend to look, there are runes carved into the marble. They are not large, and they are easy to miss, but once you notice them, they are difficult to ignore.
Halvdan.
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What are the runes in Hagia Sophia?
The runes in Hagia Sophia are a Viking inscription carved into the marble gallery, likely around the 9th-11th century. Only part of the name remains (“-ftan”), but it is widely identified as the Norse name Halvdan.
Carved around a thousand years ago in a building that, at the time, stood at the centre of both religious life and imperial power in Constantinople.
In many ways, the story only really begins much later.
For centuries, these runes were not part of the story of Hagia Sophia at all. They simply remained there, in the marble, unnoticed for what they were. It was not until 1964 that they were recognised as something more, and a few years later the Swedish runologist Elisabeth Svärdström managed to interpret them.
Today, only part of the name survives - “-ftan” - but it is enough to identify it as the Norse name Halvdan. The rest has worn away, yet most scholars agree that the original inscription likely stated that it was Halvdan himself who carved the runes.
The name itself is not unusual. Halvdan appears across the Norse world in the Viking Age, known from sagas and runestones throughout Scandinavia. It is often interpreted as “half Danish” or “man from Denmark”, but more broadly it reflects a Nordic identity shaped by kinship and language rather than anything resembling a modern nation state.
The world he came from was far from isolated.
For several centuries, Norse travellers moved eastwards along vast river systems and trade routes, particularly via the Dnieper and the Volga. These were long and demanding journeys, with ships dragged across land between waterways and passage negotiated through regions of shifting power. They brought goods from the north - furs, pelts, amber and wax - and traded for silver, silk, wine and spices. Constantinople was the greatest hub in this network, a place where goods, people and ideas converged.
For some, that journey did not end with trade.
Many began as merchants, standing at markets with furs and skins, exchanging them for goods from the south. But for a number of them, their role gradually changed.
Trade gave way to service.
Some entered the ranks of the Varangian Guard, the emperor’s elite bodyguard. It was a relatively small but highly effective force, at times numbering between 500 and 1500 men. As foreigners without ties to local factions, they were often considered more reliable than the empire’s own power groups.
At the same time, their presence was carefully controlled. The Byzantine authorities had little interest in large, independent groups of foreigners within the city walls. Norsemen entered Constantinople through defined roles - as traders, sailors or soldiers - rather than as a free, self-contained community.
This is where the areas outside the city become particularly interesting.
West of the city, around what is today Küçükçekmece, lay a Byzantine harbour known as Rhegion. Archaeological excavations in the area - often referred to as Bathonea - have in recent years revealed finds that several researchers interpret as signs of a Norse presence. Not isolated objects, but patterns that do not fit neatly into Byzantine material culture and instead point towards connections with northern traders and Varangians. The research is still ongoing, but it raises the possibility that Norsemen at times formed their own environments or temporary settlements on the outskirts of Constantinople.
Seen in that light, Halvdan becomes easier to imagine.
Not as a lone figure, but as part of a wider network of people moving between trade, settlement at the edge of the city, and service within the empire.
And then the question presents itself.
What was Halvdan actually doing there?
He is standing in Hagia Sophia, in a space closely tied to imperial authority and to the Christian world that shaped the city. Perhaps he was there as a soldier, with access through the Varangian Guard. Perhaps he was among the few northern traders allowed into the city on that particular day, exchanging furs for spices, and simply stepped into a place everyone spoke about. Or perhaps it was something much simpler - a pause, a moment, a man finding himself somewhere he would otherwise never have been.
At that time, Hagia Sophia was one of the most advanced and imposing buildings in the world, with an interior space and a dome unmatched for centuries. For a man like Halvdan, the scale of it must have been overwhelming.
We only know that, at some point, he stopped, found something sharp or pointed, and carved his runes into the marble railing.
That is all we know with certainty.
The rest remains open.
