Who was the king during the period when the first Estates-General met in France?

The meeting of the first Estates-General in France took place in 1302, during the reign of Philip IV. This king, also known as Philip the Fair, called the Estates-General to address financial issues and to seek support for his military campaigns. The Estates-General was an assembly that represented the three estates of the realm: the clergy, the nobility, and the common people. Philip IV's decision to convene this assembly marked a significant development in the relationship between the monarchy and other social classes in France, as it was an attempt to gain broader legitimacy and support for his government's policies.

Louis IX, Philip III, and Charles IX were all notable kings of France, but they ruled during different periods. Louis IX reigned from 1226 to 1270 and is known for his deep sense of justice and religious piety. Philip III ruled from 1270 to 1285, and his reign was marked by military campaigns rather than the calling of the Estates-General. Charles IX's reign (1560-1574) occurred in a much later period, well after the first meeting of the Estates-General. Thus, Philip IV is the correct response because he is the king associated with the establishment of this important institutional assembly in France.