Once you stop moving, a remarkable number of new problems present themselves. Your waste accumulates instead of being left behind, breeding the parasites and fly-borne diseases a wandering band simply walked away from. Your stored food is now visible — and seizable — to neighbours who might want it. Your children, no longer carried on the trail, can be born more often and survive in greater numbers; but each new mouth is also a vulnerability when the harvest fails and there is nowhere to roam. The skeletons from the first sedentary villages, such as those of the Natufians of the Levant around 12,000 BCE, are shorter, more diseased, and more cavity-ridden than the foragers who came before them.
The bargain of sedentism was an exchange of individual welfare for collective power. A foraging band might be healthier on average — taller, leaner, with better teeth — but a settled village could store grain against winter, raise more children, and field more warriors when threatened. Within a few generations the settlement could out-produce, out-breed, and out-defend its mobile neighbours, who had no walls to retreat behind and no granary to siege. The choice, once made, was nearly impossible to reverse: a population dependent on stored grain and tied to fields cannot simply resume walking thirty miles a week, and abandoning the village means abandoning the surplus that keeps its children alive. Sedentism also fixed what had been fluid and negotiable — your relationship to a particular patch of land, your obligations to a particular set of neighbours, your dependence on a particular store of seed. A nomadic band that quarrels can split and drift apart; villagers locked to their fields must instead invent ways to live with people they cannot leave, which is the root of formal law, the headman, the council, and the priest. From those fixities flow inheritance, boundary disputes, and the first durable inequalities, as some households accumulate more grain, more land, more standing than others, and pass it down rather than sharing it out as a mobile band must. Property, in any sense a modern lawyer would recognize, begins here — not as a law but as a fact on the ground that law would later be invented to defend.
Almost every modern political question — who owns the land, who owes whom, who counts as a citizen of which place — is a continuation of the sedentary bargain struck in those first villages. The mobility revolution of the digital era, for all its talk of borderless work and nomad visas, has not really undone it; we still expect one another to live at fixed addresses, pay tax in fixed jurisdictions, register our children in fixed districts, and belong, legally, to one country at a time. The homeless person and the refugee remain anomalies precisely because they fall outside the grid of fixed places the first sedentary villages laid down.