By the time of the Fifth Crusade, the medieval port of Acre was not only the capital of the “Kingdom of Jerusalem,” it pretty much was the kingdom. But if you had to choose one city to pretend was a whole kingdom, medieval Acre was not a bad choice.
Alexandria, Egypt had been the primary Mediterranean trade city for centuries, and of course it remained a key port. But Northern Europeans were more comfortable bringing their products to the Crusader city, where Old French was the official language and it was easy to find speakers of German or Provencal. And so Acre became the primary trading port for about a century.
Northern Europe’s key export was wool. The cold climate encouraged sheep to put on thick coats, and the entire culture was set up to process wool into cloth, from cottage spinsters to water-powered weaving mills. Europe had two other valuable products to trade: amber from the Baltic and saffron, the pollen of the crocus flower. They also exported hunting dogs and falcons.
Everything else that the medieval world valued (and was portable) tended to come from the East: other spices, gemstones, silk, glass, and ceramics. Europeans made their own glass and pottery, but it had little value next to what came from Baghdad or Egypt. Of course you could find these things in Alexandria, but if you were a Northern merchant stocking up after unloading your bolts of wool, you were already in Acre. And so more and more trade went north.
Both Alexandria and Constantinople, the other ancient trade hub, had doubled their profit by manufacturing raw materials. Soda was made locally by burning plants that had grown in salty places, so a glassmaking factory was obvious. Acre now acquired glassmakers. Cities were where the most skilled workmen could find sufficient wealthy customers, so workshops for gold and silver smithing and fine silk weaving also grew up. There was a large scriptorium that produced fine book copies.
Exports from Acre weren’t just high tech or long-range, they also included local products. Farmers brought their animals to Acre’s slaughterhouses, where the animals turned into meat, leather, parchment, and soap. Dates and sugar were also grown locally; Acre had a sugar refinery for a while.
The city became horribly overcrowded and polluted. Windows facing the port had to be kept closed or refuse might blow in. We don’t even want to know what was floating in the water. Blood from slaughterhouses, even fouler refuse from tanneries, and household sewage was all poured raw into the sea.
Trade always has a pacifying effect on a region. The Franks in Acre were highly motivated to promote peaceful travel to and from Damascus and Aleppo, which were still Ayyubid-governed cities. Most of the time, a truce was in effect and life was pretty normal. It’s hard to know how the average person in Acre felt if he heard a new Crusade had been called. Was he glad knowing that trade would spike as newcomers came through, hopeful that regained territory would add to the city’s wealth, or sorry that roads might be closed as truces collapsed? The last seems likeliest, as we see in the history of modern Europe how allowing trade to be the most important consideration set up a Common Market that sponsored Europe’s longest period of internal peace.