1. Disputed Succession of the French Throne: The French king, Charles IV, died in 1328 without a male heir. His closest relative was his cousin, Edward III, the king of England, whose mother was the sister of Charles IV. However, the French nobility preferred Philip of Valois, a cousin of Charles IV from the male line, to succeed the throne, leading to a disagreement about rightful succession. Edward III asserted his claim to the French crown, which was the trigger for the start of the conflict known as the Hundred Years' War.
2. Flanders Connection: Flanders, a prosperous and strategically important region in modern-day Belgium and France, was a significant source of fine wool for the English textile industry. The region had strong economic ties to England and was often in conflict with the French king. England supported Flemish rebels against French control, further straining relations between the two countries.
3. Feudal Issues: The English king held lands within the borders of France as a vassal of the French king. There were disputes over feudal obligations and rights related to these lands, which added to the tensions between England and France.
4. Scottish Alliance: England and Scotland were at odds during this period, and France supported the Scots in their struggle against England. This alignment further angered the English and contributed to the tensions that led to the war.
5. Economic Rivalry: Both England and France were growing economic powers, competing for trade and control of resources. These economic rivalries, combined with the other factors mentioned above, further fueled the conflict between the two nations.