Historically it has been identified that the Davis name originates from Wales (for more information check out the Davis Name Meaning).

research identifies progenitor of our line of the Davis family as being Thomas Davis, who is found in Australia in the 1850s. It is believed that Thomas was born in Australia around 1820.

The Davis ancestry goes back 6 generations and biographies exist for some members as indicated by links

• Thomas Davis abt 1820 - 1905 married Jane Bygrave 
  
  • Louisa Jane Davis 1865 - 1942 married Patrick McDermott
    • Emily Louisa McDermott married Sydney Walter Jessop
      • Esmond Early Jessop married Mary Agnes Darrough
        • My Mother

Finding Thomas has become such an obsession that I have begun an exercise to identified EVERY (or as close as I can get to it) DAVIS in NSW pre 1840. I am desperately hoping this will turn up my Thomas. As I complete my ship by ship journey, I will be updating my Davis's in Colonial NSW page

Davis is a patronymic surname originating in Wales that means 'son of St. David '.[2].  It is derived from patrynomic form of the male given name David, itself coming from the Hebrew name Dodaveha meaning 'beloved of Jehovah'   It is the 45th most common surname in England and 68th most common in Wales. It is often interchange able with Davey, Davies, Devis, Davie, Dafis, Dafys