Numerous coats of arms of various German cities, arranged in several rows on a plain background.
Coats of arms of imperial cities, from Johann Siebmachers "New Wappenbuch" , 1605
© gemeinfrei
Two lattice windows, heavily decorated on the outside, with a total of five statues on the frames, some of them wearing crowns. The house and the decorations are colourful.
"Kaiserfenster" at Ulm Town Hall
© gemeinfrei, Fotograf: Joachim Köhler
Excerpt from a historical map showing several churches and roads, with the inscription ‘Der freyen Reichs Stadt Mühlhausen’ (The Free Imperial City of Mühlhausen).
"Der freyen Reichsstadt Mühlhausen Territorium" from the Atlas Saxonicus Novus 1754
© gemeinfrei
Historical, woodcut-style depiction of two buildings, one of which is a tower. In front of it is a square with people.
Augsburg Town Hall and Perlach Tower from Merian's Topographia Sueviae
© gemeinfrei
Historical depiction of a town with gabled houses. A person is standing on the balcony of one of the houses, and numerous people are standing on the square in front of it, facing this person.
Homage of the citizens of Frankfurt to Franz I after his coronation as emperor in 1745
© gemeinfrei

Civitas imperialis - Origin - Periodization - Spatial Effects.

An information system on the phenomenon of the imperial city in the Middle Ages and the Modern Period

This research project (duration: June 1, 2025–May 31, 2026), made possible by funding from the Friedrich Christian Lesser Foundation, aims to systematically record the complex phenomenon of imperial cities in the Middle Ages and the Early Modern Period and make it publicly and academically accessible through an innovative digital information system.

Initial Situation

The term "imperial city" has been used inconsistently throughout history; attributions changed over time, and the boundaries between the group of free cities and autonomous urban communities often became blurred. Sources such as imperial registers or tax lists are incomplete or contradictory. A systematic, comparative overview that does justice to the diverse manifestations of the "Imperial City" type and provides both the temporal and spatial location of the Imperial Cities does not yet exist.

Project Objectives

The project creates a freely accessible internet portal with an interactive digital map offering the following core functions:

  • Cartographic representation of Imperial Cities across six historical periods based on the available sources (1241–1806)
  • Typological filtering according to the constitutional background of the Imperial estate (cities on Imperial property, ecclesiastical property, Imperial bailiwick cities, Free Cities)
  • Contextualization through the inclusion of imperial borders, historical transport routes, and other historical information
  • Selectable information pages on the individual cities with descriptions of their respective Imperial City status, the available sources, and a selected bibliography
  • Provision of research data in accordance with FAIR principles for subsequent use by other projects

The information system pursues three main objectives: First, to create a low-threshold, didactically well-prepared offering for schools, educational institutions, and interested laypeople. Second, the data-driven and interactive visualization enables new scholarly perspectives on the imperial cities as a complex historical phenomenon. Third, the structured publication of the underlying research data according to modern standards (FAIR principles) creates a sustainable foundation for further research. The project thus combines sound historical research with modern methods of digital history and cartography – and makes a central theme of German and European urban history accessible in a new way.

Funded by: