The map visualises how the Treaty of Verdun (843) split the Carolingian Empire created by Charlemagne into three separate kingdoms, each ruled by a son of the late Emperor Louis the Pious. The treaty ended a bitter civil war among Charlemagne’s grandsons and set the cultural fault-lines, which would later solidify into France (purple), Germany (yellow), and a short-lived Middle Kingdom (blue).
More specifically:
| Realm | Ruler (in 843) | Color |
| Francia occidentalis | Charles the Bald | Purple |
| Francia Media | Emperor Lothair I | Blue |
| Francia orientalis | Louis the German | Yellow |
Western kingdom – Francia occidentalis (purple)
- Core Frankish heartland “Francia” stretching from Rouen and Paris down to Tours and Bourges.
- Southern marches: Aquitaine, Gascony, Septimania, Spanish March/Navarre guarding the Pyrenees.
- Atlantic seaboard cities: Brest, Nantes, Bordeaux.
- Roughly anticipates the later medieval kingdom of France.
Middle kingdom – Francia media (blue)
- Northern belt Lotharingia (Aachen, Utrecht, Mainz) linking North Sea to the Alps.
- Central Burgundy (Besançon, Lyon, Geneva) and Provence (Arles, Marseille).
- Italian axis: Kingdom of Italy—Milan, Ravenna, Venice—and the Alpine corridor down to Rome (Papal States remain grey and independent).
- A long, corridor-shaped realm intended to give the emperor sea-to-sea control.
Eastern kingdom – Francia orientalis (yellow)
- Germanic stem-duchies: Saxony (Hamburg, Bremen), Thuringia, Franconia, Swabia (Ulm, St Gall), Bavaria, Carinthia.
- Eastern frontier faces the Moravian Kingdom and Slavic lands; Prague lies just beyond the red border.
- Foreshadows the later Holy Roman Empire’s German core.
Map take-aways
- The single Carolingian Empire has been carved into three colour-coded kingdoms, each following major ethnic and geographic blocs.
- Internal frontiers run north–south, while the outer imperial border (red) still encircles much of Western Europe.
- Lothair’s elongated middle strip—linking the North Sea to central Italy.
