After the Viking invasions in France during the 9th and 10th century invasions, the state was extremely crippled and in need of good leadership. When the last Carolingian king died in 987, a man named Hugh Capet took over, creating the dynasty of the Capetian Kings. One of these kings was Phillip II Augustus, the man that created the France we know today.
Hugh Capet was the first king in the Capetian dynasty. However he was only a king in name, like many of his successors. He did not hold any more power than a lord who participated in feudalism. Hugh chose his son, Robert the Pious (r. 996-1031), to be his successor. True to the title given to him, he did not engage in war during his reign.
After Robert’s death, his sons fought for the right of successor. This battle lasted from 1031-1039, and greatly weakened what little was left of the French monarchy.
Once the sons came to their senses, they realized that they needed to bring the area outside of France, Île-de-France, under their control if they truly wanted to have the power of kings. They accomplished this through political marriages and taking the lands of dead vassals who had no successors. They also dispossessed vassals who were proven to be unfaithful to their oaths.
Phillip II Augustus (r. 1226-1270), was the most influential and important king of the Capetian dynasty. He defeated the Angevin Empire, which were the territories that belonged to the House of Plantagenet (a bloodline), and crushed King John of England. From there he turned France into one of the most dominant powers of Europe. He reformed the country, turning it into the France we know today.
As you can see, Phillip II Augustus was the one who reformed France, but his predecessors did some of the hard work to make it possible. It is safe to say that without the Capetian Dynasty, the sophisticated France we are so familiar with may not have existed.
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