Black Sea ports of the Golden Horde according to Casti­lian “Libro del conosçimiento de todos los reynos” of the 14th century

Objective: This study aims to investigate the localization and reconstruct the potestary symbols of Black Sea ports that were subject to the sovereign authority of the Golden Horde in the 14th century. Based on this analysis, the research assesses the potential for the formation of the Golden Horde’s thalassocracy. Research materials: The research draws from various sources, including the Castilian “Libro del conosçimiento de todos los reynos” from the 14th century, preserved in four copies Z, N, S, and R. Additionally, it utilizes compass maps of the Black Sea created by Venetian masters Petrus Vesconte (1313), Perrino Vesconte (1321), and Mallorca’s cartographer Angelino Dulcert (1330, 1339). Byzantine periplus records of the Black Sea from the 14th to 15th centuries, Claudius Ptolemy’s “Cosmography” in a revision by Byzantine monk Maximus Planudes around 1300 AD, as well as EDB and GIS data from Tabula imperii Bizantini are also incorporated. Results and novelty of the research: The analysis of the Castilian ”Libro del conosçimiento de todos los reynos” has unveiled a previously unrecognized structure: the “Black Sea’s vexillographic portolan chart.” This portolan chart provides comprehensive descriptions of the locations of ports along the Black Sea coast, indicating the sovereign’s standards of the rulers of these port cities. In the majority of cases, the sovereign mentioned is Uzbek khan (1313–1341), under whose rule the original and now lost holotype of this remarkable portolan was compiled. Both the port names and the depictions of standards in this portolan reflect geographical and vexillographical inaccuracies of the time, as acknowledged by the Castilian compilers of the four preserved copies. By identifying the topoi and standards described in the “Black Sea’s vexillographic portolan,” a reconstruction of the Black Sea’s map, which includes all ports, shipping routes, and symbols of power related to the Golden Horde sovereign’s authority, was achieved. The final observations indicate that over 80% of the Black Sea waters were under the control of the Golden Horde, even during the reign of Uzbek khan, offering a unique opportunity for the emergence of a new thalassocracy.