The evolution of the monetary systems of the Black Sea region and the Balkans in the XIII-XV centuries.

The states of the Balkans and the Black Sea region minted different coins and had different traditions in maintaining the currency system. The comparative study of these coins was necessary to demonstrate that changes affecting the currencies were determined by the genesis of the worldwide economic system and have appeared because the medieval financial approaches were universal. One thing was common for those dissimilar currencies: specie existed for the use of the authorities and of the subjects concurrently. Published and unpublished documents together with quantitative data obtained during the numismatic analysis allowed to find and to describe dates and circumstances of dozens reforms in the Byzantine and Tartar states, to reconstruct the ideology of medieval financiers. The first and the second gave us also names of the coins, their parameters, values, rates and cross-rates, different characteristics of the monetary fund as a whole. They were calculated with the use of original methods developed for the numismatic study based on the probability theory and reflecting the statistical nature of the numismatic material. The results accumulated in this book are not merely the description of the evolution of the financial systems in the region, they are the tool necessary for the research of the economic history of the Levant in the Middle Ages.