Theoderich

Also known as Theodericus, Theoderic the Pilgrim

German Christian pilgrim, probably a Bavarian monk, whose Libellus de Locis Sanctis is the most architecturally detailed surviving description of Jerusalem under the Latin kingdom.

Theoderich is one of those medieval authors known almost entirely through the prologue of his single surviving book. He was a German cleric — likely a monk and possibly to be identified with the bishop Theoderich of Würzburg — who travelled to the Holy Land between roughly 1169 and 1174 and afterwards composed the Libellus de Locis Sanctis as a memorial of what he had seen.

What sets him apart is his eye for buildings. He counted columns and bays in the Holy Sepulchre, transcribed inscriptions in the Templum Domini and Templum Salomonis, paced out the dimensions of the Templar headquarters and the Hospital, and produced a description so technically precise that nineteenth- and twentieth-century archaeologists used the text to reconstruct portions of the rotunda before its 1808 fire and reconstruction.

Read alongside John of Würzburg, his slightly earlier compatriot, Theoderich gives us the most concentrated documentary picture we possess of Jerusalem in the twenty years before Hattin — and the indispensable point of comparison against which the post-1187 Muslim-built city must be measured.

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