Researchers, including scholars from the University of Gothenburg, have mapped the travel patterns of 25 emperors who ruled the Holy Roman Empire. The study shows that these journeys were undertaken strategically to maintain imperial power, and that travel routes changed as that power weakened.
The Holy Roman Empire was founded in 962, when the German king Otto I was crowned emperor. The empire, which primarily encompassed present-day Germany, Austria, the Czech Republic, and parts of Italy, played an important role in European politics during the Middle Ages and the early modern period before being dissolved in 1806.
Unlike modern states, the Holy Roman Empire was not a unified nation but consisted of many self-governing principalities. Previous research on state formation has often focused on modern territorial states and has therefore overlooked the fact that power in the medieval period was personal and mobile.
"Because the Holy Roman Empire lacked a centralized bureaucracy, emperors depended on travel to exercise control over local powerholders. This meant they constantly had to make strategic decisions about where their presence would have the greatest impact," says Andrej Kokkonen, Professor of Political Science.
Together with researchers from the London School of Economics and Political Science and Aarhus University, he examined how emperors decided where to travel and what political considerations shaped their itineraries. By analyzing more than 72,000 dated and geographically identified documents, such as royal decrees and charters, the researchers reconstructed the travel routes of 25 Holy Roman emperors during the period 919-1519.
"Our strategy was to exploit a historical turning point, the so-called Great Interregnum between 1250 and 1273, when imperial power collapsed. By comparing emperors' travel patterns before and after this period, we identified how changes in the balance of power influenced their behavior," says Andrej Kokkonen.
Strong emperors avoided their relatives - weak ones sought them out
The results are clear. Before 1250, when imperial power was strong, emperors were less likely to travel to areas controlled by their own relatives.
"They were considered sufficiently loyal. After the Interregnum, from 1273 onward, emperors' travel patterns changed abruptly. They then spent more time in territories controlled by their family."
According to the researchers, this may be because weaker emperors could no longer take family loyalty for granted. Instead, close relatives, especially male heirs and potential rivals, became key targets of imperial control. The analyses also show that these effects were strongest in economically important regions, underscoring that both political and material incentives shaped travel over the 600 years covered by the study.
A new perspective on power and the state in premodern Europe
The study thus shows that imperial presence was not evenly distributed across the territory but was selective and strategic. The emperor was not merely a symbolic figure, but a mobile institution whose physical presence constituted the core of governance in the Holy Roman Empire.
The findings also have broader implications.
"Our research is relevant for modern authoritarian systems as well. By linking historical material to contemporary political science theory, we show that political control always depends on relationships, resources, and presence - whether exercised on horseback in the Middle Ages or through institutions in modern states," says Andrej Kokkonen.
