Medieval knights ran an early international bank so pilgrims didn't have to carry gold

A pilgrim heading to Jerusalem could deposit money with the Knights Templar in Europe and withdraw an equivalent sum from a Templar house in the Holy Land, using sealed letters of credit instead of hauling coin through bandit-ridden roads. The network, built to protect Crusader-era travelers, functioned much like a modern international bank centuries before one formally existed.

— Dan Jones, The Templars: The Rise and Spectacular Fall of God's Holy Warriors — 2017
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