At the time of the Norman Conquest there were in existence in England some thirty-five autonomous monasteries of black monks. There were no other monastic houses in the country, and none of the existing abbeys had any connection with a foreign mother-house; neither had they any dependencies under their control. Nor did any kind of federation or interdependence exist between the English houses; indeed, so far as the scanty evidence goes, even the bond of common origin or tradition which, less than a century before, had to a certain extent grouped together the filiations of Glastonbury, Abingdon and Ramsey had by 1066 ceased to have any kind of influence.

These monasteries were as a body very wealthy. It has been calculated that their aggregate income was £ 11,066, or almost a sixth of the total actual revenue in England in 1086, though the potential wealth of the country, and even to some extent its actual wealth, was much greater than appears in Domesday, for the Great Survey takes no real account of the lands north of the Humber and Mersey, and in every English county there were very considerable tracts of land lying uncultivated, which were exploited in one way or another within the two following centuries. As it was, however, the monasteries possessed a very considerable portion of the land, and to their wealth in land must be added their wealth in treasure and ornaments of every description, which made of their churches a wonder alike to Danes and Normans.