Giambologna (1529-1698), court sculptor to the Medici, was famed for his depictions of animals, either in combat or repose. The present bronze is the rarer of two types of bulls attributed to the master. For a discussion of the two types, see C. Avery, Giambologna - The Complete Sculpture, Oxford, 1987, pp. 269-270, nos. 143-143, fig. 67.