Final answer:
Catherine de' Medici is credited with bringing several dancing masters from Italy to France, greatly influencing the prominence of court ballet in French culture.
Step-by-step explanation:
The person credited with bringing several dancing masters from Italy to France and beginning the long reign of the court ballet is Catherine de' Medici. She was a member of one of Italy's royal families who married into the French monarchy.
Catherine de' Medici brought significant cultural influence to France, including the introduction of sophisticated dance masters and the enrichment of the French court's ballet tradition. Not to be confused with Marie de' Medici, another prominent Italian who married into the French royal family, but is known for commissioning the Marie de' Medici cycle of paintings by Peter Paul Rubens.