Scott Alexander (author/host)

When the French went up to engage him, Henry attempted to withdraw, took up a position on good ground, and when the French attacked, the English broke them utterly.

Halfway through the battle, the order was given to kill the prisoners instead of holding them for ransom, and so the battle was not merely a defeat for the French, but a disaster, with a generation's worth of military leaders dead in a single day.

Here's an image showing the Battle of Agincourt, with various battle-like activities going on.

The caption reads, and then they all died.

The disaster was made worse by the fact that the French nobility at the time of Agincourt were trapped in an internal feud that was rapidly coming to resemble civil war.

Between the time of the battles of Crecy and of Poitiers, Philip the Fortunate had given the rich duchy of Burgundy in fief to his faithful son Philip the Bold.

But Philip was faithful to his father, not to France.

As the years rolled on and the throne of France passed from Philip the Fortunate to his son and grandson, the interests of the Dukes of Burgundy began to diverge from those of the kings of France, and so in the age of the long truce, the bold Dukes of Burgundy won lands through conquest and through marriage until their wealth and power nearly matched that of their ostensible monarchs.

Under the three great dukes of Burgundy who ruled in sequence, their realm became the leading state of the Renaissance, the continent's greatest sponsor of art and music, and the true cultural heartland of Europe.

Footnote.

To pick an element purely because I happen to know something about it, we have dance manuals in the 15th century from two places, Italy and Burgundy.

They don't show up elsewhere in Europe until the 16th century, or for laggardly places like England, the 17th.

Back to the text.

But all these accomplishments had been won by the power of the Kingdom of France, which during the pause in the Hundred Years' War had cheerfully spent men and treasure conquering and protecting these lands for the Burgundians, allowing them to spend their treasure on paintings and sculptures and dance manuals.

The Kingdom of France had done this not by the will of the King of France, Charles VI, Philip the Fortunate's grandson, who at that time was seriously mentally ill, and who the year before his regency started had murdered several people in a paranoid fit and afterwards took to believing that he was made of glass and would shatter if he fell, but through the decision of his regent, one Philip the Bold, Duke of Burgundy.

Footnote about the King being seriously mentally ill.

Wikipedia helpfully tells us that it may have been any or all of, quote, end quote.

Back to the text.

Naturally, Philip had opponents at court who objected to his abuse of the treasury for his private purposes.

They wanted to abuse the treasury for their private purposes, and it simply wasn't fair that Uncle Philip got to monopolise it all.