I love this page Etymologically Speaking…with its curious list origins of English, French, German and Spanish words. Shame he or she hasn’t written any more.
This is what it says about cerveza:
This term, which means “beer” in Spanish, originally came from the medieval French word cervoise. For its part, the French term origianlly stemmed from the Gallo-Roman (that is, ancient French-Latin dialect) word cerevisia, which was used in honor of Ceres, the Roman goddess of the harvest. It is interesting to note that just about the time that the Spanish were adopting the term cerveza (aroung 1482), the French started to drop cervoise in favor of the term biere– from the Germanic term Bier (from the Latin biber, “to drink”), which was the term that was more popular in northern Europe, where the climate was more favorable to the production of the grains that were used to make the beverage. [(A footnote: the reader might be wondering what term was used in Spain before the adoption of cerveza. Before 1482, the inhabitants of the Iberian Peninsula had used the completely-unrelated ancient Iberian word ceria or celia, meaning "fermented wheat.")(Footnote #2: The English term ale comes from the Scandinavian term for beer, oel. Although oel collectively refers to all types of beer, you beer purists out there know that the English term ale came to refer only to beer produced using the "top" fermentation process. Beer produced using the "bottom" fermentation process is called lager.)].