Wealth from land provided, in all probability, the initial capital for the Sienese merchant bankers trading in commodities like grain, wool and textiles; the Gallerani were no exception. Their ability to determine the abundance or lack of specific staples or commodities and move them across Europe or further afield was, most likely, the start of their fortune and prosperity. They would buy, for example, wool in England, which would be shipped to Flanders or Italy for the production of cloth, and the final products could end as far away as the Levant. The merchants, who had already begun to diversify into banking, found their opportunities for wealth creation increased even more when the Church taxes began to flow through their coffers hugely boosting the company's cash-flow and trading capacity. I am trying to identify the cash flow of the Gallerani family, as well as the interest and exchange rates they applied, by analysis of the documentation and the surviving ledgers.
This interdisciplinary project connects three of the most important commercial regions of Medieval Europe: Flanders, England and Tuscany. It will also help to fill the hiatus in our knowledge of 13th-century financial history, the incompleteness of which has already been pointed out by Spufford (1988) and de Roover (1948). I will challenge the prevailing, yet un-founded, view that the Church accepted some degree of interest on loans by the analysis of hard data. Determining actual exchange and interest rates will show how the usury laws were implemented in practice, and not how they should have worked, given the Churchs teaching on usury.