The Creation of France

In 1217, Philip II Augustus’ son, Louis VIII (1187 – 1226), began to nibble away at Guyenne, the part of the old duchy of Aquitaine still in English hands. Louis died young, but his capable widow, Blanche of Castile (1188 – 1252), as regent for her son, Louis IX (1214 – 1270), continued his efforts to increase the power of the French kings.  Peter of Dreux, the husband of Alix of Brittany, and regent for Duke Jean I of Brittany (c. 1218 – 1286), refused to recognise the coronation of Louis. Blanche raised an army and brought the rebels, who included the counts of Champagne and Lusignan, to heel.

Blanche was also the driving force behind the 1229 Treaty of Paris, by which the counts of Toulouse accepted French suzerainty.

Another treaty of Paris, this time dating 1259, compounded the differences between Louis IX and Henry III of England (1207 – 1272). Henry ceded his claims to Anjou, Maine and Poitou (within Aquitaine) but retained the title of Duke of Aquitaine and parts of Guyenne and Gascony. He also retained the duchy of Normandy’s islands, now called the Channel Islands (Jersey, Guernsey, Aldernay and Sark). Later, Agenais was restored to Henry.  

Henry accepted that, for the French territories, Louis was his overlord. This was a recipe for long-term friction.

The Hundred Years’ War, between England and France had its roots in this division of lands in the geographic territory of France being subject to claims of inheritance by the kings of England.