The core of Mainz's lordship in the Eichsfeld: the castle of the Rusteberg above the Leine, named as a Mainz administrative seat in 1132, and Heiligenstadt with its collegiate church of St Martin and an old royal palace, a market settlement with a merchants' hall and an advocate's residence that becomes a chartered town only in 1227.
Around it Mainz has enfeoffed the Gleichen counts with castles (Gleichenstein), and the counts of Lohra hold advocacies (Bischofstein, Worbis); to the north the Welfs and Quedlinburg's Duderstadt.
Who he is
- Title
- The archbishop's officers of the Rusteberg (the later vicedominate of the Eichsfeld)
- Since
- The Rusteberg is named as a seat of Mainz administration in 1132
- Confidence
- low
de.wikipedia Rusteberg; Heilbad Heiligenstadt
Overlord
Archbishop Conrad of Mainz.
What it holds
- The Rusteberg
- Heiligenstadt and St Martin's
- Overlordship of the Gleichen fiefs in the Eichsfeld
How it was acquired
Mainz possessions in the Eichsfeld from the early Middle Ages.
Allies and rivals
The counts of Gleichen (vassals), the counts of Lohra, the Welfs to the north.
How things stand that morning
Held by Mainz's castellans; neutral under Conrad.
Wealth
The Leine valley road from Göttingen to the Werra; Heiligenstadt's market.
Military
The Rusteberg. No numbers.
Threats
- The Welf lands to the north
- A split in Mainz after October 1200
Places of note
- The Rusteberg: Mainz castle (coordinates approximate)
Where the sources disagree
Evidence: Officers not named for 1200.
On the map: The 1200 extent of Mainz's Eichsfeld is uncertain; only the core is drawn.
Primary sources for Mainz
Chronicles, registers, sagas and inscriptions written in or near 1200 that cover this entry. Each has its own page with editions, translations and where to read it.
- Annals of Marbach (compiled to 1238, the section on 1198 to 1210 written in the early 13th century). Alsatian annals on the Staufen side of the Upper Rhine. Read online
- Chronicle of Burchard of Ursberg, Burchard of Ursberg (about 1229 to 1230, reworked by Conrad of Lichtenau). Written a generation later by a fierce partisan of the Staufen and a critic of Innocent III. Read online
- Chronicle of Otto of St Blasien, Otto of St Blasien (about 1209 to 1210). A Swabian continuation of Otto of Freising written from the Staufen side. Read online
- Chronicle of Reinhardsbrunn; Chronicle of St Peter's, Erfurt (Erfurt chronicle in the 13th century; Reinhardsbrunn compilation about 1340 to 1349 from older annals). The two Thuringian chronicles. Read online
- Royal Chronicle of Cologne (in stages from about 1175 to about 1250; the section on 1198 to 1220 written soon after the events). The fullest German narrative of the throne war from the Welf and Cologne side. Read online
- Regesta Imperii V: calendar of the acts of Philip, Otto IV and Frederick II, 1198 to 1272 (calendar of documents of 1198 to 1272, published 1881 to 1901). A dated calendar of every known act of King Philip and King Otto IV, with the acts of popes and princes that bear on the Empire. Read online
- Register of Innocent III on the affair of the Roman Empire, Innocent III and the papal chancery (1198 to 1209, compiled as a separate register at the curia). The pope's own file on the German throne war: letters to and from Philip, Otto, the German princes and bishops, and the famous Deliberatio of late 1200 or early 1201 in which Innocent weighs the claims of Frederick, Philip and Otto before deciding for Otto. Read online
- The Registers of Pope Innocent III for 1199 to 1201, Innocent III and the papal chancery (22 February 1199 to 21 February 1201). The pope's outgoing letters for the year, in his chancery's own copy, touching nearly every realm in the atlas. Read online
1 more in the sources library for The Rhineland, the Low Countries and the Swiss Lands.
Sources and studies
Last revised 4 November 2026. Published 4 November 2026. Suggest a correction on the OMNIA Discord.