There are many reasons to leave one's home country. Curiosity, a thirst for adventure and the pursuit of economic success are positive incentives; negative causes include fleeing war, oppression or famine.
In the late Middle Ages, many peasants fled from servitude by noble landowners and sought their personal freedom in the cities. There was also work for many people there.
Hamburg benefited in a special way from such newcomers. Dutch merchants fleeing the war of independence raging in their homeland, or Jews from Portugal, persecuted for their faith settled here from the 16th century onwards. They continued their business from their new home and thus promoted Hamburg's long-distance trade to a particular extent. Hamburg's development into a global trading city began in the Middle Ages when Hamburg joined the Hanseatic League, an alliance of North German merchants and cities.