There is evidence that, at least from the a.d. 2nd century, the vocabulary and phonology of Roman Tarraconensis was different from the <answer>rest of Roman Hispania</answer>. Differentiation has arisen generally because Spanish, Asturian, and Galician-Portuguese share certain peripheral archaisms (Spanish hervir, Asturian/Portuguese ferver vs. Catalan bullir, Occitan bolir "to boil") and innovatory regionalisms (Sp novillo, Ast nuviellu vs. Cat torell, Oc taurèl "bullock"), while Catalan has a shared history with the Western Romance innovative core, especially Occitan.
What area was Roman Tarraconensis language different from?
rest of Roman Hispania