Family History and Genealogy Resources by Surname
Wallis Surname Origin
The same as Wales or Welch, and formed thus--Gaulish, Wallish, Wallis, and also Welsh or Welch, a name given to the Britons by their Danish and Angles invaders, because they originally came from Gaul.
Source: An Etymological Dictionary of Family and Christian Names With an Essay on their Derivation and Import; Arthur, William, M.A.; New York, NY: Sheldon, Blake, Bleeker & CO., 1857.
Wallis Surname Meaning and Family Facts
There is more to Wallis family history than the origin of your surname:
A Wallis Family History Thought:
'The only thing new in the world is the history you don't know.' --Harry S. Truman