July 2016 - Louis VII's son, Philippe Auguste, was much more ambitious and smarter than his father. Philippe came to the throne in 1180 AD, when he was only fourteen years old. He began well by marrying a woman who brought a rich part of France called Artois as her dowry, so he had more power and more money than his father had. Then Philippe encouraged Richard and John of England to fight against their father, Henry, so as to weaken England's hold on French territory in Normandy and Aquitaine. Philippe went on the Third Crusade, in 1188 AD (when he was 22), but came home early to continue pushing the English out of France. Richard's early death made this much easier, because John was not a good soldier. After Friedrich Barbarossa's death in 1190, Germany fell into civil war, which also helped Philippe get more power. In 1212, he sent an army into the south of France on the Albigensian Crusade, killing tens of thousands of Cathars. With control over the south of France, the French kings became much, much richer. Money flowed from the south to the north, paying for the great cathedrals. By the time Philippe died in 1223, at the age of 61, he had created a loyal civil service which administered and oversaw every province of his kingdom, all over France.
Philippe's son Louis VIII took over when Philippe died, and continued the Albigensian crusade. When he won, in 1226, Louis VIII forced Count Raymond of Toulouse to marry his daughter to one of Louis' sons, so that the French kings took over the direct rule of Toulouse (because Raymond had no sons, his daughter inherited his property). But Louis died later that same year.
Because Louis VIII died young, in 1226, his son, Louis IX, was only twelve years old. Louis IX's mother, Blanche of Castile (Eleanor of Aquitaine's granddaughter), ruled for him until he grew up. Blanche was a good ruler. Many people in France didn't like her, because she was originally from Spain. Some lords thought this was a good chance to rebel and get back their independence. But it was too late. The king's armies were too strong for them, and the lords were not united enough to overcome him.
Louis IX convinced pretty much everyone in France that it was always better to follow the king. He was so religious that he became a saint after he died, and today we usually call him Saint Louis. Because he was so Christian, he wanted to hurt French people who were Jewish, but his mother protected the Jewish people. St. Louis went on two crusades, the Seventh Crusade and the Eighth Crusade. When he got back from the Seventh Crusade, he brought a crown of thorns with him, and he built a famous chapel in Paris called the Sainte Chapelle to hold it. He died in Tunis on the Eighth Crusade in 1270, probably of dysentery. Both Crusades were failures. Fortunately his mother Blanche kept on ruling France for him while he was away.
St. Louis' descendants were not as well loved as he and Blanche were. They put in more and more taxes, and were not as concerned with justice. The beginning of the Little Ice Age was making it harder for farmers to grow good crops. But the French people still wanted to follow their kings, Louis's son Philippe III (1270-1285) and his grandson Philippe IV (1285-1314), who finally replaced the old Roman fort in Paris and built the Conciergerie. The lords could never unite against the king as they did in England, and if they could not unite the alternative to the kings was civil war, which nobody wanted. In 1290, when Edward made all the Jews leave England, many of them settled in France, still protected by Blanche of Castile's old policies.
Philippe IV had three sons, Louis X (1314-1316), Philippe V (1316-1322), and Charles IV (1322-1328), but they all died young without leaving sons of their own. All three men had daughters, but - even though Blanche had done such a good job - the French lords refused to accept a woman as their official ruler, or even the sons of these women, Philippe IV's grandsons through their mothers. Instead, they chose one of Charles' cousins, Philippe of Valois, to be the next king. He was a grandson of Philippe IV, but through his father. The king of England, Edward III, was also a grandson of Philippe IV through his father, and he said he had as much right to the throne as Philippe of Valois did. When Edward attacked France to enforce his right to the throne, the Hundred Years' War began.