There are other variations on this tradition, for example that the test was to have a fire burning in the hearth by the following morning and the squatter could then extend the land around by the distance they could throw an axe from the four corners of the house.
From a period spanning the 17th to the beginning of the 19th centuries, the expansion of the Welsh population combined with poverty brought about a series of incidents of squatting on isolated patches of land in the most rural parts of Wales.
This legendary belief may bear some relation to genuine folk customs and actual practices by squatters encroaching on common or waste land.
[1] The tradition may have provided squatters with a sense that their actions enjoyed some legitimacy conferred by an older code of laws more in tune with values of social justice than the supposed "Norman yoke".
These may in fact be properties that were originally built by squatters and may be constructed in a vernacular building tradition using locally available materials.
The Welsh woodland charity Coed Cymru used Tŷ Unnos as a name for a house design using local materials.