After 1066, William did not attempt to integrate his separate domains into one unified realm with one set of laws. His seal from after 1066, of which six impressions still survive, was made for him after he conquered England and stressed his role as king, while separately mentioning his role as duke. When in Normandy, William acknowledged that he owed fealty to the French king, but in England no such acknowledgment was made – further evidence that the various parts of William's lands were considered separate. The administrative machinery of Normandy, England, and Maine continued to exist separate from the other lands, with each one retaining its own forms. For example, England continued the use of writs, which were not known on the continent. Also, the charters and documents produced for the government in Normandy differed in formulas from those produced in England.