Agricultural development led early societies to settle. Settlements required growing food and a lasting source of water. That's why these early civilizations were born around rivers. The proximity of rivers facilitated access to fertile soil and, logically, to water.
Once a civilization has a stable source of food it can start growing surplus of it, which creates the possibility of trade. That is, stable food production is a base for the complexification of a society that can lead to the creation of other jobs, like the merchant.
It also enables a society to complexify its social structures, to build cities, to develop religion and culture which creates more jobs.
Because of widespread fear of a strong central government at the time they were written and strong loyalties among Americans to their own state as opposed to any national government during the American Revolution, the Articles of Confederation purposely kept the national government as weak as possible .