The powerful Borromeo family were merchants at San Miniato on the main trade route between Florence and Pisa around 1300. After a failed rebellion against Florentine rule in 1370, when Filippo di Lazzaro Borromei was hanged as one of the ringleaders, they fled the town and settled in other parts of Italy. By the late fourteenth and early fifteenth centuries there were three main branches of the family, one in Milan, a second in Venice, and a third in Florence. There were also major banking companies in all three places headed by members of the family.
Vitaliano Borromeo was given citizenship of Milan in 1416. He built up a trading empire and established a banking service that was expanded by his Filippo, his only son. In January 1436, the latter established a branch of their Bruges bank in England naming it Filippo Borromei e Compagni di Londra. Their business dealings must have been taken place in Lombard Street or nearby. The banks handled the northern end of the family’s European-wide exchange and commercial business. The company’s London ledger has survived for the period between 1436 and 1439 offering a precise oversight of the facilities the bank offered for trade and exchange between London, the Low Countries, and Italy.