The book deals with a singular primary source relevant to Istrian medieval history, the catalogue of rights of the patriarchs of Aquileia in Istria. Since the document is originally undated, there were numerous attempts at chronologically framing and interpreting the catalogue. Based on extensive archival research, the author has managed to offer a new dating of the document, convincingly demonstrating that it was drawn up in the chancellery of the Aquileian patriarch Raymond della Torre in October of 1280. The document is then analyzed within this new chronological framework based on the methodological principles of the Cambridge School of contextualism. A tour de force of Istrian medieval history, the book offers a thickly annotated account of a tumultuous period in which multiple forces clashed for the supremacy over the Istrian peninsula.