[1] A 14th-century document from the cartulary of Malton priory refers to John as brother of Serlo de Burgo, but contemporary evidence indicates this is probably false.
[2] John, who was apparently born by 1056, seized the mill of Vains, Normandy in 1076.
The King's Court of William I of England ruled against the seizure, returning the mill to the Abbey of Mont-Saint-Michel.
[3][4] In the 1086 Domesday survey as 'John, nephew of Waleran', he was reported holding Carbrooke, Hunstanton, Ringstead, Rushford, Saxlingham, Thurton, Walpole (St Andrew and St Peter) in Norfolk and Elsenham in Essex.
He also held as tenant in chief: Brettenham, Griston and West Carbrooke in Norfolk.