Recorded in the Domesday Book of 1086 as a tenant-in-chief of William the Conqueror holding a number of manors in Somerset with caput at Dunster Castle.
Participating in the Norman conquest of England, he was granted fifty-five manors in Somerset, one each in Wiltshire and Dorset.
[6] He acquired sixty-eight manors in the west of England, one each in Devon, Wiltshire, eleven in Dorset, one of them Ham, which was inherited by his descendants, it was called Ham-Mohun, or Hammoon, and fifty-five in Somerset.
He bred horses both at Cutcombe and at Nunney, near Frome, sub-infeudated (through one of his tenants), where unbroken brood-mares were kept.
Between 1090 and 1100 he granted the Church of St. George at Dunster (where part of the Norman building survives), land and tithes and a tenth of his mares, to the Abbey of St. Peter at Bath and to Bishop John de Villula (died 1122), to "build and exalt" the church.