1000 and 1500, Deventer grew to be a flourishing trade city because of its harbour on the river IJssel, which was capable of accommodating large ships. The city eventually joined the Hanseatic League.

One of the commodities it traded in, dried haddock and cod from Norway, gave the citizens the nickname they carry to this day: "Deventer Stokvis". In the 15th century, Deventer had a common mint, where coins for the three IJssel cities Deventer, Zwolle,