Some of the first archaeological evidence of landscape boundaries dates back to England around 1,500 BCE, but 500 years later it also appears in the rest of northwestern Europe, all the way to the Baltic countries.
     "From being a predominantly open landscape with large commons with scattered trees and bushes, the landscape became dominated by linear demarcation lines," says Mette Lovschal, doctoral student at Denmark's Aarhus University. Lovschal's study covers classical archaeological excavation plans, aerial photos and scans of soil surfaces from all of Northwestern Europe.
     In the Iron Age, around 500 BCE, people also started to fence in their houses and gather in small villages, which were protected with hedges and embankments. "The next couple of centuries saw a massive boom of fences," she reveals. "Suddenly, people had all sorts of fences, for instance fences made out of large poles and palisades, embankments, moats, large ditch systems and Caesar's lilies. They experimented with all these forms of demarcation."
     Caesar's lilies consist of broad belts of 5 to 8 rows of closely-spaced, open holes. Pointed stakes were sometimes put in between the holes to form a fence. The Roman general Caesar also met this type of defence when he conquered present-day France, hence the name.
     The boundaries not only provided functional protection, but also became symbols of power. "At the fenced farms we see that some farms have a significantly larger and stronger fence than others," she explains. "For instance, in Hodde in western Jutland (150 BCE), one of the farms stands out by being placed highest up in the terrain, but also by being the farm with the longest stables, the finest ceramics and the largest fence."
     Lovschal also says that while one generation would build large palisades and fortifications, the next generation would tear them down. This shows that the power structures were rather inconstant. "Whereas at one point only a few farms were fenced, eventually all farms became fenced. The population density had probably increased and the climate had worsened. This resulted in an increased pressure on the resources in the Celtic society." The period was marked by heavy conflict and looting.

Edited from ScienceNordic (2 January 2013)