The Domesday entry for Charmouth in 1086, describes it as “Cernemude” - the mouth of the river Cerne where there may have been a small harbour.
Sixteen Salt Workers were employed there boiling the Sea Water in large shallow open Lead Pans until the water evaporated and the salt removed. It may well have gone back to Roman times with its proximity to the Roman road, where the Street is today. The industry was carried on all along the Dorset Coast and there is a reference in 774 to a Salt House in Lyme Regis owned by Sherbourne Abbey. The main use of the salt was to preserve food for the winter months and was one of the first traded products and would have been carried by packhorse or boat. The Lord of the Manor at this time was Robert, Count of Mortain in Normandy, who was William the Conqueror's half brother and fought with him in 1066. He held over six hundred other manors, including 71 in Dorset. Below him were a number of tenants in chief who after his death in 1091 formed separate Manors. Another French nobleman, William De Estre is shown as the Lord of the Manor of Charmouth. It is his grandson, Richard who was to later give the village to Forde Abbey in 1170.

This is the entry in the Domesday Book for “Cernemude” as Charmouth was known by in 1086. Robert holds Cernemude from the Count. Algar held it before. It paid tax for 3 hides. Land for 3 hides. Land for 3 ploughs. In lordship 2 ploughs, 3 slaves; 3 villagers with 2 ploughs. 16 salt-workers. Meadow 16 acres; pasture 3 furlongs long and 1 furlong wide; woodland 7 furlongs long and 1 furlong wide. Value 60s.

The Count held 71 manors in Dorset including Catherstone and Wootton Fitzpaine

The Count of Mortain. Robert, half-brother of King William and younger brother of Bishop Odo of Bayeux. He held more land in England than any other follower of King William He was the greatest lay landholder in Dorset where he held 71 manors including Catherstone and Wootton Fitzpaine.After rebelling against William Rufus in 1088, he was reconciled and died in 1091. When his fief escheated to the King, many of his noblemen became tenants-in-chief, their lands forming separate baronies. Later fees were described as of Morton, Montague or Montacute; among the principal later holders were the Beauchamps. Mortain is in the departement of Manche in France.

An early depiction of the process of making Salt using a furnace. Salt Workers boiled the Sea Water in large shallow open Lead Pans until the water evaporated and the salt removed.

Cernemunde' - Charmouth - is recorded in the Domesday Book of 1086. The name Charmouth derives from the ancient Cernemude - the mouth of the (river) Cerne. It is probable that the name represented a far wider area at the time. The river is now to narrow for navigation but there might have been a small harbour at its mouth. The primary activity at the time concerned the production of salt. 16 saltworkers were recorded working for the Count of Montain at Charmouth, suggesting perhaps a minor coastal settlement—possibly now eroded by the sea [VCH, iii, 88]. The industry would certainly appear to have been carried on into the 12th century, as a grant of 1172 x 1205 to the abbey concerns a tenement 'for making salt, keeping a boat or other purposes. The street the main road of the village is of pre-Roman origin an ancient route that ran from the east to Axmouth, the southern end of the Fosse Way.