The royal manor of Winnianton, which was held by King William I at the time of the Domesday Book (1086), was also the head manor of the hundred of Kerrier and the largest estate in Cornwall. It was assessed as having fifteen hides before 1066. At the time of Domesday there was land for sixty ploughs, but in the lord's land there were two ploughs and in the lands held by villeins twenty-four ploughs. There were twenty-four villeins, forty-one freedmen, thirty-three smallholders and fourteen slaves. There was , eight square leagues of pasture and half a square league of woodland. The livestock was fourteen unbroken mares, three cattle and one hundred and twenty-eight sheep (in total 145 beasts); its value was £12 annually. 11 of the hides were held by the Count of Mortain and there is more arable and pasture and 13 more persons are recorded: Rinsey, Trelowarren, Mawgan-in-Meneage and seventeen other lands are also recorded under Winnianton.