Feudal system
The feudal system was a European hierarchical social system based on service to a social superior. For the lower classes, the service was usually manual labour. Those above them in the system usually owed military service. Position within the hierarchy was normally determined by birth. Although the system had some flexibilities, notably through the institutions of the Church and the free towns (boroughs, burghs), its rigidity brought inefficiencies. The Black Death is often credited with hastening its end.
The English legal system, in accordance with its common practice, has never formally abolished the feudal system, preferring to abolish just its practical consequences. Thus the Queen legally still "owns" all the land in England, with the de facto owners being officially her feudal tenants, directly or indirectly. This "ownership" gives her almost no legal rights over the land: she owns gold and silver deposits, swans, whales and sturgeon.