Was there ever a ruling class? Social and economic mobility in England, 1200-2010

"Using surnames we follow the socio-economic status of elites and underclasses in England all the way from 1066 to 2011. Paradoxically we find two things. The first is that England does not have, and never had, a persistent ruling elite. Social mobility in the long run for the indigenous English and western European migrants has been complete. The second, however, is that mobility rates are much lower than social scientists conventionally measure, and have increased little between the middle ages and now. There is one big change between the years before and after 1850. Before then elites had higher fertility than the poor. Since then elite groups display much lower fertility, so that the permanent effect of a period spent at the social summit is a reduction in number of descendants, even when the group returns to average status."