The Tribunal of Thebes roughly covers the area controlled by the Byzantine Empire around 800, excluding its Italian possessions, but including Greece and most of Asia Minor. Boundaries have been contested at times.
This tribunal is detailed in The Sundered Eagle: The Theban Tribunal. Additional information relating to its history can be found in the section covering House Jerbiton in Houses of Hermes: Societas. That same book also lists more than one magical tradition that originated from the area, if not still residing there in the section covering House Ex Miscellanea. A small amount of information related to Trianoma and her sister, both of whom were from the area, in the House Bonisagus section of Houses of Hermes: True Lineages. Another small amount of information can be found in the House Tremere section of the same book, discussing conflicts between House Tremere and the magi living in the Tribunal of Thebes.