Can a city develop without exterior trading?

Question

I’m exploring different scenarios for a future D&D campaign. I want to know if it’s possible, for a growing settlement, to develop without trading with its neighbors.

Let’s assume that they can grow their population through immigration, and that all resources needed for a proper civilization can be found within their territory (metals, wood, food, water, stone, room for growth, ...)

As for a justification for no exterior trading, let’s say that the society in question doesn’t want to allow anyone who isn’t a citizen (or future citizen) within their borders.

I’m wondering if there have been such examples in real life, and if any of them were successful.

EDIT1: I used the term “city” because this is for a land that is being settled for the first time, it will eventually grow into a whole country, but I assumed that one would first develop one city. By “city” I mean buildings/habitations/... that are under the influence of one administrative center that the city is built around.

Answer 1

Even Sakoku in Japan was not complete.

Sakoku (鎖国, "closed country") was the isolationist foreign policy of the Japanese Tokugawa shogunate (aka Bakufu)1 under which, for a period of over 220 years, relations and trade between Japan and other countries were severely limited, nearly all foreign nationals were barred from entering Japan and common Japanese people were kept from leaving the country. The policy was enacted by the Tokugawa shogunate under Tokugawa Iemitsu through a number of edicts and policies from 1633 to 1639, and ended after 1853 when the American Black Ships commanded by Matthew Perry forced the opening of Japan to American (and, by extension, Western) trade through a series of treaties.

because

Japan traded at this time with five entities, through four "gateways". The largest was the private Chinese trade at Nagasaki (who also traded with the Ryūkyū Kingdom), where the Dutch East India Company was also permitted to operate. The Matsumae clan domain in Hokkaidō (then called Ezo) traded with the Ainu people. Through the Sō clan daimyō of Tsushima, there were relations with Joseon-dynasty Korea. Ryūkyū, a semi-independent kingdom for nearly all of the Edo period, was controlled by the Shimazu clan daimyō of Satsuma Domain. Tashiro Kazui has shown that trade between Japan and these entities was divided into two kinds: Group A in which he places China and the Dutch, "whose relations fell under the direct jurisdiction of the Bakufu at Nagasaki" and Group B, represented by the Korean Kingdom and the Ryūkyū Kingdom, "who dealt with Tsushima (the Sō clan) and Satsuma (the Shimazu clan) domains respectively".[3]

And this is perhaps the closest in human history that a developed country came to trying to stop all trade.

The lesson to be learned is that there is always a bigger jerk in the world. America was big enough and powerful enough to impose its will on Japan, and to force it to trade (be looted, in other words).

Eventually, if you keep developing, you will reach a size and a wealth level that becomes attractive to another country, that will want to 'share' your wealth.

Answer 2

Any isolation from the neighboring towns will be only temporary for two reasons.

1. Politics. As the kinglets of the various towns attempt to influence each other over issues of the day (borders, water supplies, orc control, etc.) alliances are important. Trade concessions are part of the influence toolbox, along with arranged marriages, intrigue, bribery, gifts, military campaigns, etc. Trade can be an inexpensive method of influence...and has the side effect of bringing in duty revenue.

2. Economics. The Law of Comparative Advantage explains how folks' average quality of life generally improves from trade. The folks in the isolated town aren't stupid - they will hear tales about how the other towns are wealthier and many good there are cheaper. And soon some will start to smuggle those goods...which is trade.

Answer 3

First, your assumption that settlement of a vacant land (or land occupied by non-urbanized natives) would begin with anything resembling a city is probably false. You need only look at historical examples of such settlement, such as the colonization of the Americas. In what would become the US & Canada, the colonists didn't start by building cities, they started with small farms and villages, and sometimes trading posts. (As with the Hudson's Bay Company.) Cities, or even significant towns, didn't develop until much later. In Mexico and Peru, the colonists took over the pre-existing native cities.

Second, and more fundamental, barring some magical source of food, no city can survive without some sort of trade with an agricultural hinterland, even if that trade is of the elemental "you serfs give us food and we won't kill you" sort.

Answer 4

If there are locations close enough that trade is practical, there will be trade, even if it's smuggling. Some people will benefit from it, and even if they agree with the idea of keeping out foreigners, they can manage by being the ones to go to the other place, or rationalize that because these foreigners are here illegally, they won't stay so it doesn't really count.

Answer 5

Cities aren't planned they're managed, they're often always the byproduct of early trading posts or fortifications. Modern cities evolving from nothing or built from scratch do exist but have special circumstance. Washington DC and Brasilia were planned capitals.