Final answer:
Male dancers, known as danseurs nobles, were prominent in ballet during the 17th to 19th centuries, especially under the patronage of King Louis XIV and throughout the Rococo era.
Step-by-step explanation:
The period in which pro male dancers, or danseurs nobles, took leading roles in ballets predominately spanned across the 17th to the 19th centuries. During the reign of King Louis XIV, who was a significant patron of the arts from 1643 to 1715, ballet started to formalize, with male dancers in the limelight, as the king himself was an accomplished dancer. In the 18th century, the era of Rococo saw a flourish in the arts, including ballet, where male dancers continued to hold prominent roles. By the 19th century, ballet had evolved together with music, resulting in the creation of full-fledged ballet productions, where male dancers often starred in leading roles.