Sulis was a
Celtic goddess worshipped in and around the area of
Bath,
England. As with most Celtic goddesses, she had a largely protective, maternal
role to the Celtic people, best demonstrated in her nature as a goddess of healing and
therapy. Sulis was associated with
wells and natural springs, and many shrines to her and other healing goddesses (such as
Brigantia) have been found near these sites.
After the Romans contacted the Celtic people in Britain, worship of the goddess at Bath continued. Not only was it tolerated, it was encouraged by the Romans, who were fascinated and attracted to Sulis and her powers. The Romans came to equate her with their own goddess Minerva, and inscriptions found at Bath often refer to "Sulis Minerva" as a single deity, showing that the two societies' religious traditions could sometimes be united in a way which satisfied all involved.
The worship of healing goddesses around springs is not entirely coincidential: in many cases the mineralized water which issued from these sources actually did have therapeutic powers, and was almost always cleaner than water sources such as rivers and lakes.
Sources
Green, Miranda. The Gods of the Celts. Dover: Alan Sutton Publishing 1996.
Ross, Anne. Pagan Celtic Britain. New York: Columbia University Press 1967.