I was able to find this: "Portuguese, Galician, and Spanish: habitational name from any of the places in Spain and Portugal called Viana."
source:
www.ancestry.com/name-origin?surname=viana
In which case, what does the place name mean? I found Wikipedia pages for the places
http://en.wikipedia.org/wiki/Viana ...but I cannot locate any meaning or etymology for the place names, unless it stems from what I found below.
I don't know how accurate this is, but according to this baby name site, Viana means 'alive' and comes from Latin. If this is true, then perhaps it is a form or contraction of
Viviana? Even a short form/nick name? Since 'viana' is the 'second part' of the name.
http://babynamesworld.parentsconnect.com/meaning_of_Viana.html