Wallington, a common English place and family name, has two main known meanings coming from two different time periods, one is from the Anglo-Saxon invasion of Albion and the Norman conquest of England.
Anglo-Saxon Origin The name "Wallington" derives from the Anglo Saxon "Waletone" meaning "village of the Britons". This would be so, as the Anglo-Saxons settled more and more into Albion the native British peoples where segregated into their own villages to begin with. These villages were known as a "Waletone" or "Wallington" as it is known now. A member of this village was also known as a "Wallington".
Norman Origin In old French "Wallington" means defender of the castle, but the theory that's being proposed now is the "Wallingtons" from the British Isles migrated to Brittany as the Anglo-Saxons spread further into the British Islands.
This migration happened around the years 500 to 600 AD so a native Briton could have settled in France and the meaning of the word "Waletone" could have changed as French progressed to the meaning defender of the castle. A Wallington was also recorded of accompany William the Conqueror when he invaded England. And could have defended a castle in England as he did back in Normandy.
The reason for the lack of "Wallingtons" in France is because of the Hundred Year War between England and France, the "Wallington" migrated back to England. Thus as time went on as the British Empire came into being the "Wallington" name spread globally.
Waller- A man on the walls Ton- A heavy fortified town or castle